Age Owner Branch data TLA Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * clauses.c
4 : : * routines to manipulate qualification clauses
5 : : *
6 : : * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7 : : * Portions Copyright (c) 1994, Regents of the University of California
8 : : *
9 : : *
10 : : * IDENTIFICATION
11 : : * src/backend/optimizer/util/clauses.c
12 : : *
13 : : * HISTORY
14 : : * AUTHOR DATE MAJOR EVENT
15 : : * Andrew Yu Nov 3, 1994 clause.c and clauses.c combined
16 : : *
17 : : *-------------------------------------------------------------------------
18 : : */
19 : :
20 : : #include "postgres.h"
21 : :
22 : : #include "access/htup_details.h"
23 : : #include "catalog/pg_language.h"
24 : : #include "catalog/pg_operator.h"
25 : : #include "catalog/pg_proc.h"
26 : : #include "catalog/pg_type.h"
27 : : #include "executor/executor.h"
28 : : #include "executor/functions.h"
29 : : #include "funcapi.h"
30 : : #include "miscadmin.h"
31 : : #include "nodes/makefuncs.h"
32 : : #include "nodes/multibitmapset.h"
33 : : #include "nodes/nodeFuncs.h"
34 : : #include "nodes/subscripting.h"
35 : : #include "nodes/supportnodes.h"
36 : : #include "optimizer/clauses.h"
37 : : #include "optimizer/cost.h"
38 : : #include "optimizer/optimizer.h"
39 : : #include "optimizer/plancat.h"
40 : : #include "optimizer/planmain.h"
41 : : #include "parser/analyze.h"
42 : : #include "parser/parse_coerce.h"
43 : : #include "parser/parse_func.h"
44 : : #include "rewrite/rewriteHandler.h"
45 : : #include "rewrite/rewriteManip.h"
46 : : #include "tcop/tcopprot.h"
47 : : #include "utils/acl.h"
48 : : #include "utils/builtins.h"
49 : : #include "utils/datum.h"
50 : : #include "utils/fmgroids.h"
51 : : #include "utils/json.h"
52 : : #include "utils/jsonb.h"
53 : : #include "utils/jsonpath.h"
54 : : #include "utils/lsyscache.h"
55 : : #include "utils/memutils.h"
56 : : #include "utils/syscache.h"
57 : : #include "utils/typcache.h"
58 : :
59 : : typedef struct
60 : : {
61 : : ParamListInfo boundParams;
62 : : PlannerInfo *root;
63 : : List *active_fns;
64 : : Node *case_val;
65 : : bool estimate;
66 : : } eval_const_expressions_context;
67 : :
68 : : typedef struct
69 : : {
70 : : int nargs;
71 : : List *args;
72 : : int *usecounts;
73 : : } substitute_actual_parameters_context;
74 : :
75 : : typedef struct
76 : : {
77 : : int nargs;
78 : : List *args;
79 : : int sublevels_up;
80 : : } substitute_actual_srf_parameters_context;
81 : :
82 : : typedef struct
83 : : {
84 : : char *proname;
85 : : char *prosrc;
86 : : } inline_error_callback_arg;
87 : :
88 : : typedef struct
89 : : {
90 : : char max_hazard; /* worst proparallel hazard found so far */
91 : : char max_interesting; /* worst proparallel hazard of interest */
92 : : List *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
93 : : } max_parallel_hazard_context;
94 : :
95 : : static bool contain_agg_clause_walker(Node *node, void *context);
96 : : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
97 : : static bool contain_subplans_walker(Node *node, void *context);
98 : : static bool contain_mutable_functions_walker(Node *node, void *context);
99 : : static bool contain_volatile_functions_walker(Node *node, void *context);
100 : : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
101 : : static bool max_parallel_hazard_walker(Node *node,
102 : : max_parallel_hazard_context *context);
103 : : static bool contain_nonstrict_functions_walker(Node *node, void *context);
104 : : static bool contain_exec_param_walker(Node *node, List *param_ids);
105 : : static bool contain_context_dependent_node(Node *clause);
106 : : static bool contain_context_dependent_node_walker(Node *node, int *flags);
107 : : static bool contain_leaked_vars_walker(Node *node, void *context);
108 : : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
109 : : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
110 : : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
111 : : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
112 : : static Node *eval_const_expressions_mutator(Node *node,
113 : : eval_const_expressions_context *context);
114 : : static bool contain_non_const_walker(Node *node, void *context);
115 : : static bool ece_function_is_safe(Oid funcid,
116 : : eval_const_expressions_context *context);
117 : : static List *simplify_or_arguments(List *args,
118 : : eval_const_expressions_context *context,
119 : : bool *haveNull, bool *forceTrue);
120 : : static List *simplify_and_arguments(List *args,
121 : : eval_const_expressions_context *context,
122 : : bool *haveNull, bool *forceFalse);
123 : : static Node *simplify_boolean_equality(Oid opno, List *args);
124 : : static Expr *simplify_function(Oid funcid,
125 : : Oid result_type, int32 result_typmod,
126 : : Oid result_collid, Oid input_collid, List **args_p,
127 : : bool funcvariadic, bool process_args, bool allow_non_const,
128 : : eval_const_expressions_context *context);
129 : : static List *reorder_function_arguments(List *args, int pronargs,
130 : : HeapTuple func_tuple);
131 : : static List *add_function_defaults(List *args, int pronargs,
132 : : HeapTuple func_tuple);
133 : : static List *fetch_function_defaults(HeapTuple func_tuple);
134 : : static void recheck_cast_function_args(List *args, Oid result_type,
135 : : Oid *proargtypes, int pronargs,
136 : : HeapTuple func_tuple);
137 : : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
138 : : Oid result_collid, Oid input_collid, List *args,
139 : : bool funcvariadic,
140 : : HeapTuple func_tuple,
141 : : eval_const_expressions_context *context);
142 : : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
143 : : Oid input_collid, List *args,
144 : : bool funcvariadic,
145 : : HeapTuple func_tuple,
146 : : eval_const_expressions_context *context);
147 : : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
148 : : int *usecounts);
149 : : static Node *substitute_actual_parameters_mutator(Node *node,
150 : : substitute_actual_parameters_context *context);
151 : : static void sql_inline_error_callback(void *arg);
152 : : static Query *substitute_actual_srf_parameters(Query *expr,
153 : : int nargs, List *args);
154 : : static Node *substitute_actual_srf_parameters_mutator(Node *node,
155 : : substitute_actual_srf_parameters_context *context);
156 : : static bool pull_paramids_walker(Node *node, Bitmapset **context);
157 : :
158 : :
159 : : /*****************************************************************************
160 : : * Aggregate-function clause manipulation
161 : : *****************************************************************************/
162 : :
163 : : /*
164 : : * contain_agg_clause
165 : : * Recursively search for Aggref/GroupingFunc nodes within a clause.
166 : : *
167 : : * Returns true if any aggregate found.
168 : : *
169 : : * This does not descend into subqueries, and so should be used only after
170 : : * reduction of sublinks to subplans, or in contexts where it's known there
171 : : * are no subqueries. There mustn't be outer-aggregate references either.
172 : : *
173 : : * (If you want something like this but able to deal with subqueries,
174 : : * see rewriteManip.c's contain_aggs_of_level().)
175 : : */
176 : : bool
8889 tgl@sss.pgh.pa.us 177 :CBC 4750 : contain_agg_clause(Node *clause)
178 : : {
179 : 4750 : return contain_agg_clause_walker(clause, NULL);
180 : : }
181 : :
182 : : static bool
183 : 5612 : contain_agg_clause_walker(Node *node, void *context)
184 : : {
185 [ + + ]: 5612 : if (node == NULL)
186 : 9 : return false;
187 [ + + ]: 5603 : if (IsA(node, Aggref))
188 : : {
7618 189 [ - + ]: 560 : Assert(((Aggref *) node)->agglevelsup == 0);
6756 bruce@momjian.us 190 : 560 : return true; /* abort the tree traversal and return true */
191 : : }
3185 andres@anarazel.de 192 [ + + ]: 5043 : if (IsA(node, GroupingFunc))
193 : : {
194 [ - + ]: 6 : Assert(((GroupingFunc *) node)->agglevelsup == 0);
195 : 6 : return true; /* abort the tree traversal and return true */
196 : : }
7618 tgl@sss.pgh.pa.us 197 [ - + ]: 5037 : Assert(!IsA(node, SubLink));
8889 198 : 5037 : return expression_tree_walker(node, contain_agg_clause_walker, context);
199 : : }
200 : :
201 : : /*****************************************************************************
202 : : * Window-function clause manipulation
203 : : *****************************************************************************/
204 : :
205 : : /*
206 : : * contain_window_function
207 : : * Recursively search for WindowFunc nodes within a clause.
208 : : *
209 : : * Since window functions don't have level fields, but are hard-wired to
210 : : * be associated with the current query level, this is just the same as
211 : : * rewriteManip.c's function.
212 : : */
213 : : bool
5586 214 : 4113 : contain_window_function(Node *clause)
215 : : {
4265 216 : 4113 : return contain_windowfuncs(clause);
217 : : }
218 : :
219 : : /*
220 : : * find_window_functions
221 : : * Locate all the WindowFunc nodes in an expression tree, and organize
222 : : * them by winref ID number.
223 : : *
224 : : * Caller must provide an upper bound on the winref IDs expected in the tree.
225 : : */
226 : : WindowFuncLists *
5586 227 : 1150 : find_window_functions(Node *clause, Index maxWinRef)
228 : : {
229 : 1150 : WindowFuncLists *lists = palloc(sizeof(WindowFuncLists));
230 : :
231 : 1150 : lists->numWindowFuncs = 0;
232 : 1150 : lists->maxWinRef = maxWinRef;
233 : 1150 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
234 : 1150 : (void) find_window_functions_walker(clause, lists);
235 : 1150 : return lists;
236 : : }
237 : :
238 : : static bool
239 : 10257 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
240 : : {
241 [ + + ]: 10257 : if (node == NULL)
242 : 113 : return false;
243 [ + + ]: 10144 : if (IsA(node, WindowFunc))
244 : : {
245 : 1561 : WindowFunc *wfunc = (WindowFunc *) node;
246 : :
247 : : /* winref is unsigned, so one-sided test is OK */
248 [ - + ]: 1561 : if (wfunc->winref > lists->maxWinRef)
5586 tgl@sss.pgh.pa.us 249 [ # # ]:UBC 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
250 : : wfunc->winref);
251 : : /* eliminate duplicates, so that we avoid repeated computation */
2958 tgl@sss.pgh.pa.us 252 [ + + ]:CBC 1561 : if (!list_member(lists->windowFuncs[wfunc->winref], wfunc))
253 : : {
254 : 3110 : lists->windowFuncs[wfunc->winref] =
255 : 1555 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
256 : 1555 : lists->numWindowFuncs++;
257 : : }
258 : :
259 : : /*
260 : : * We assume that the parser checked that there are no window
261 : : * functions in the arguments or filter clause. Hence, we need not
262 : : * recurse into them. (If either the parser or the planner screws up
263 : : * on this point, the executor will still catch it; see ExecInitExpr.)
264 : : */
5586 265 : 1561 : return false;
266 : : }
267 [ - + ]: 8583 : Assert(!IsA(node, SubLink));
268 : 8583 : return expression_tree_walker(node, find_window_functions_walker,
269 : : (void *) lists);
270 : : }
271 : :
272 : :
273 : : /*****************************************************************************
274 : : * Support for expressions returning sets
275 : : *****************************************************************************/
276 : :
277 : : /*
278 : : * expression_returns_set_rows
279 : : * Estimate the number of rows returned by a set-returning expression.
280 : : * The result is 1 if it's not a set-returning expression.
281 : : *
282 : : * We should only examine the top-level function or operator; it used to be
283 : : * appropriate to recurse, but not anymore. (Even if there are more SRFs in
284 : : * the function's inputs, their multipliers are accounted for separately.)
285 : : *
286 : : * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
287 : : */
288 : : double
1891 289 : 168661 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
290 : : {
2643 andres@anarazel.de 291 [ - + ]: 168661 : if (clause == NULL)
2643 andres@anarazel.de 292 :UBC 0 : return 1.0;
2643 andres@anarazel.de 293 [ + + ]:CBC 168661 : if (IsA(clause, FuncExpr))
294 : : {
295 : 26434 : FuncExpr *expr = (FuncExpr *) clause;
296 : :
6292 tgl@sss.pgh.pa.us 297 [ + + ]: 26434 : if (expr->funcretset)
1891 298 : 23897 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
299 : : }
2643 andres@anarazel.de 300 [ + + ]: 144764 : if (IsA(clause, OpExpr))
301 : : {
302 : 1595 : OpExpr *expr = (OpExpr *) clause;
303 : :
6292 tgl@sss.pgh.pa.us 304 [ + + ]: 1595 : if (expr->opretset)
305 : : {
306 : 3 : set_opfuncid(expr);
1891 307 : 3 : return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
308 : : }
309 : : }
2643 andres@anarazel.de 310 : 144761 : return 1.0;
311 : : }
312 : :
313 : :
314 : : /*****************************************************************************
315 : : * Subplan clause manipulation
316 : : *****************************************************************************/
317 : :
318 : : /*
319 : : * contain_subplans
320 : : * Recursively search for subplan nodes within a clause.
321 : : *
322 : : * If we see a SubLink node, we will return true. This is only possible if
323 : : * the expression tree hasn't yet been transformed by subselect.c. We do not
324 : : * know whether the node will produce a true subplan or just an initplan,
325 : : * but we make the conservative assumption that it will be a subplan.
326 : : *
327 : : * Returns true if any subplan found.
328 : : */
329 : : bool
8776 tgl@sss.pgh.pa.us 330 : 29570 : contain_subplans(Node *clause)
331 : : {
332 : 29570 : return contain_subplans_walker(clause, NULL);
333 : : }
334 : :
335 : : static bool
336 : 91212 : contain_subplans_walker(Node *node, void *context)
337 : : {
338 [ + + ]: 91212 : if (node == NULL)
339 : 2624 : return false;
7792 340 [ + + ]: 88588 : if (IsA(node, SubPlan) ||
5714 341 [ + - ]: 88546 : IsA(node, AlternativeSubPlan) ||
7794 342 [ + + ]: 88546 : IsA(node, SubLink))
6756 bruce@momjian.us 343 : 167 : return true; /* abort the tree traversal and return true */
8776 tgl@sss.pgh.pa.us 344 : 88421 : return expression_tree_walker(node, contain_subplans_walker, context);
345 : : }
346 : :
347 : :
348 : : /*****************************************************************************
349 : : * Check clauses for mutable functions
350 : : *****************************************************************************/
351 : :
352 : : /*
353 : : * contain_mutable_functions
354 : : * Recursively search for mutable functions within a clause.
355 : : *
356 : : * Returns true if any mutable function (or operator implemented by a
357 : : * mutable function) is found. This test is needed so that we don't
358 : : * mistakenly think that something like "WHERE random() < 0.5" can be treated
359 : : * as a constant qualification.
360 : : *
361 : : * This will give the right answer only for clauses that have been put
362 : : * through expression preprocessing. Callers outside the planner typically
363 : : * should use contain_mutable_functions_after_planning() instead, for the
364 : : * reasons given there.
365 : : *
366 : : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
367 : : * but not into SubPlans. See comments for contain_volatile_functions().
368 : : */
369 : : bool
8045 370 : 78568 : contain_mutable_functions(Node *clause)
371 : : {
372 : 78568 : return contain_mutable_functions_walker(clause, NULL);
373 : : }
374 : :
375 : : static bool
2865 376 : 55857 : contain_mutable_functions_checker(Oid func_id, void *context)
377 : : {
378 : 55857 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
379 : : }
380 : :
381 : : static bool
8045 382 : 198586 : contain_mutable_functions_walker(Node *node, void *context)
383 : : {
8645 384 [ + + ]: 198586 : if (node == NULL)
385 : 1210 : return false;
386 : : /* Check for mutable functions in node itself */
2865 387 [ + + ]: 197376 : if (check_functions_in_node(node, contain_mutable_functions_checker,
388 : : context))
389 : 4359 : return true;
390 : :
382 alvherre@alvh.no-ip. 391 [ - + ]: 193017 : if (IsA(node, JsonConstructorExpr))
392 : : {
382 alvherre@alvh.no-ip. 393 :UBC 0 : const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
394 : : ListCell *lc;
395 : : bool is_jsonb;
396 : :
397 : 0 : is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
398 : :
399 : : /*
400 : : * Check argument_type => json[b] conversions specifically. We still
401 : : * recurse to check 'args' below, but here we want to specifically
402 : : * check whether or not the emitted clause would fail to be immutable
403 : : * because of TimeZone, for example.
404 : : */
405 [ # # # # : 0 : foreach(lc, ctor->args)
# # ]
406 : : {
407 : 0 : Oid typid = exprType(lfirst(lc));
408 : :
409 [ # # # # ]: 0 : if (is_jsonb ?
410 : 0 : !to_jsonb_is_immutable(typid) :
411 : 0 : !to_json_is_immutable(typid))
412 : 0 : return true;
413 : : }
414 : :
415 : : /* Check all subnodes */
416 : : }
417 : :
24 amitlan@postgresql.o 418 [ + + ]:GNC 193017 : if (IsA(node, JsonExpr))
419 : : {
420 : 117 : JsonExpr *jexpr = castNode(JsonExpr, node);
421 : : Const *cnst;
422 : :
423 [ - + ]: 117 : if (!IsA(jexpr->path_spec, Const))
24 amitlan@postgresql.o 424 :UNC 0 : return true;
425 : :
24 amitlan@postgresql.o 426 :GNC 117 : cnst = castNode(Const, jexpr->path_spec);
427 : :
428 [ - + ]: 117 : Assert(cnst->consttype == JSONPATHOID);
429 [ - + ]: 117 : if (cnst->constisnull)
24 amitlan@postgresql.o 430 :UNC 0 : return false;
431 : :
24 amitlan@postgresql.o 432 [ + + ]:GNC 117 : if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
433 : : jexpr->passing_names, jexpr->passing_values))
434 : 81 : return true;
435 : : }
436 : :
333 michael@paquier.xyz 437 [ + + ]:CBC 192936 : if (IsA(node, SQLValueFunction))
438 : : {
439 : : /* all variants of SQLValueFunction are stable */
440 : 229 : return true;
441 : : }
442 : :
2466 tgl@sss.pgh.pa.us 443 [ - + ]: 192707 : if (IsA(node, NextValueExpr))
444 : : {
445 : : /* NextValueExpr is volatile */
2466 tgl@sss.pgh.pa.us 446 :UBC 0 : return true;
447 : : }
448 : :
449 : : /*
450 : : * It should be safe to treat MinMaxExpr as immutable, because it will
451 : : * depend on a non-cross-type btree comparison function, and those should
452 : : * always be immutable. Treating XmlExpr as immutable is more dubious,
453 : : * and treating CoerceToDomain as immutable is outright dangerous. But we
454 : : * have done so historically, and changing this would probably cause more
455 : : * problems than it would fix. In practice, if you have a non-immutable
456 : : * domain constraint you are in for pain anyhow.
457 : : */
458 : :
459 : : /* Recurse to check arguments */
2865 tgl@sss.pgh.pa.us 460 [ - + ]:CBC 192707 : if (IsA(node, Query))
461 : : {
462 : : /* Recurse into subselects */
3810 tgl@sss.pgh.pa.us 463 :UBC 0 : return query_tree_walker((Query *) node,
464 : : contain_mutable_functions_walker,
465 : : context, 0);
466 : : }
8045 tgl@sss.pgh.pa.us 467 :CBC 192707 : return expression_tree_walker(node, contain_mutable_functions_walker,
468 : : context);
469 : : }
470 : :
471 : : /*
472 : : * contain_mutable_functions_after_planning
473 : : * Test whether given expression contains mutable functions.
474 : : *
475 : : * This is a wrapper for contain_mutable_functions() that is safe to use from
476 : : * outside the planner. The difference is that it first runs the expression
477 : : * through expression_planner(). There are two key reasons why we need that:
478 : : *
479 : : * First, function default arguments will get inserted, which may affect
480 : : * volatility (consider "default now()").
481 : : *
482 : : * Second, inline-able functions will get inlined, which may allow us to
483 : : * conclude that the function is really less volatile than it's marked.
484 : : * As an example, polymorphic functions must be marked with the most volatile
485 : : * behavior that they have for any input type, but once we inline the
486 : : * function we may be able to conclude that it's not so volatile for the
487 : : * particular input type we're dealing with.
488 : : */
489 : : bool
150 490 : 1126 : contain_mutable_functions_after_planning(Expr *expr)
491 : : {
492 : : /* We assume here that expression_planner() won't scribble on its input */
493 : 1126 : expr = expression_planner(expr);
494 : :
495 : : /* Now we can search for non-immutable functions */
496 : 1126 : return contain_mutable_functions((Node *) expr);
497 : : }
498 : :
499 : :
500 : : /*****************************************************************************
501 : : * Check clauses for volatile functions
502 : : *****************************************************************************/
503 : :
504 : : /*
505 : : * contain_volatile_functions
506 : : * Recursively search for volatile functions within a clause.
507 : : *
508 : : * Returns true if any volatile function (or operator implemented by a
509 : : * volatile function) is found. This test prevents, for example,
510 : : * invalid conversions of volatile expressions into indexscan quals.
511 : : *
512 : : * This will give the right answer only for clauses that have been put
513 : : * through expression preprocessing. Callers outside the planner typically
514 : : * should use contain_volatile_functions_after_planning() instead, for the
515 : : * reasons given there.
516 : : *
517 : : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
518 : : * but not into SubPlans. This is a bit odd, but intentional. If we are
519 : : * looking at a SubLink, we are probably deciding whether a query tree
520 : : * transformation is safe, and a contained sub-select should affect that;
521 : : * for example, duplicating a sub-select containing a volatile function
522 : : * would be bad. However, once we've got to the stage of having SubPlans,
523 : : * subsequent planning need not consider volatility within those, since
524 : : * the executor won't change its evaluation rules for a SubPlan based on
525 : : * volatility.
526 : : *
527 : : * For some node types, for example, RestrictInfo and PathTarget, we cache
528 : : * whether we found any volatile functions or not and reuse that value in any
529 : : * future checks for that node. All of the logic for determining if the
530 : : * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
531 : : * belongs in this function. Any code which makes changes to these nodes
532 : : * which could change the outcome this function must set the cached value back
533 : : * to VOLATILITY_UNKNOWN. That allows this function to redetermine the
534 : : * correct value during the next call, should we need to redetermine if the
535 : : * node contains any volatile functions again in the future.
536 : : */
537 : : bool
8045 538 : 1351297 : contain_volatile_functions(Node *clause)
539 : : {
540 : 1351297 : return contain_volatile_functions_walker(clause, NULL);
541 : : }
542 : :
543 : : static bool
2865 544 : 340701 : contain_volatile_functions_checker(Oid func_id, void *context)
545 : : {
546 : 340701 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
547 : : }
548 : :
549 : : static bool
8045 550 : 2968051 : contain_volatile_functions_walker(Node *node, void *context)
551 : : {
552 [ + + ]: 2968051 : if (node == NULL)
553 : 88723 : return false;
554 : : /* Check for volatile functions in node itself */
2865 555 [ + + ]: 2879328 : if (check_functions_in_node(node, contain_volatile_functions_checker,
556 : : context))
557 : 851 : return true;
558 : :
2466 559 [ - + ]: 2878477 : if (IsA(node, NextValueExpr))
560 : : {
561 : : /* NextValueExpr is volatile */
2466 tgl@sss.pgh.pa.us 562 :UBC 0 : return true;
563 : : }
564 : :
1112 drowley@postgresql.o 565 [ + + ]:CBC 2878477 : if (IsA(node, RestrictInfo))
566 : : {
567 : 541955 : RestrictInfo *rinfo = (RestrictInfo *) node;
568 : :
569 : : /*
570 : : * For RestrictInfo, check if we've checked the volatility of it
571 : : * before. If so, we can just use the cached value and not bother
572 : : * checking it again. Otherwise, check it and cache if whether we
573 : : * found any volatile functions.
574 : : */
575 [ + + ]: 541955 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
576 : 341141 : return false;
577 [ + + ]: 200814 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
578 : 4 : return true;
579 : : else
580 : : {
581 : : bool hasvolatile;
582 : :
583 : 200810 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
584 : : context);
585 [ + + ]: 200810 : if (hasvolatile)
586 : 32 : rinfo->has_volatile = VOLATILITY_VOLATILE;
587 : : else
588 : 200778 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
589 : :
590 : 200810 : return hasvolatile;
591 : : }
592 : : }
593 : :
594 [ + + ]: 2336522 : if (IsA(node, PathTarget))
595 : : {
596 : 161828 : PathTarget *target = (PathTarget *) node;
597 : :
598 : : /*
599 : : * We also do caching for PathTarget the same as we do above for
600 : : * RestrictInfos.
601 : : */
602 [ + + ]: 161828 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
603 : 138097 : return false;
604 [ - + ]: 23731 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
1112 drowley@postgresql.o 605 :UBC 0 : return true;
606 : : else
607 : : {
608 : : bool hasvolatile;
609 : :
1112 drowley@postgresql.o 610 :CBC 23731 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
611 : : context);
612 : :
613 [ - + ]: 23731 : if (hasvolatile)
1112 drowley@postgresql.o 614 :UBC 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
615 : : else
1112 drowley@postgresql.o 616 :CBC 23731 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
617 : :
618 : 23731 : return hasvolatile;
619 : : }
620 : : }
621 : :
622 : : /*
623 : : * See notes in contain_mutable_functions_walker about why we treat
624 : : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
625 : : * SQLValueFunction is stable. Hence, none of them are of interest here.
626 : : */
627 : :
628 : : /* Recurse to check arguments */
2865 tgl@sss.pgh.pa.us 629 [ + + ]: 2174694 : if (IsA(node, Query))
630 : : {
631 : : /* Recurse into subselects */
3810 632 : 2974 : return query_tree_walker((Query *) node,
633 : : contain_volatile_functions_walker,
634 : : context, 0);
635 : : }
8045 636 : 2171720 : return expression_tree_walker(node, contain_volatile_functions_walker,
637 : : context);
638 : : }
639 : :
640 : : /*
641 : : * contain_volatile_functions_after_planning
642 : : * Test whether given expression contains volatile functions.
643 : : *
644 : : * This is a wrapper for contain_volatile_functions() that is safe to use from
645 : : * outside the planner. The difference is that it first runs the expression
646 : : * through expression_planner(). There are two key reasons why we need that:
647 : : *
648 : : * First, function default arguments will get inserted, which may affect
649 : : * volatility (consider "default random()").
650 : : *
651 : : * Second, inline-able functions will get inlined, which may allow us to
652 : : * conclude that the function is really less volatile than it's marked.
653 : : * As an example, polymorphic functions must be marked with the most volatile
654 : : * behavior that they have for any input type, but once we inline the
655 : : * function we may be able to conclude that it's not so volatile for the
656 : : * particular input type we're dealing with.
657 : : */
658 : : bool
150 659 : 278 : contain_volatile_functions_after_planning(Expr *expr)
660 : : {
661 : : /* We assume here that expression_planner() won't scribble on its input */
662 : 278 : expr = expression_planner(expr);
663 : :
664 : : /* Now we can search for volatile functions */
665 : 278 : return contain_volatile_functions((Node *) expr);
666 : : }
667 : :
668 : : /*
669 : : * Special purpose version of contain_volatile_functions() for use in COPY:
670 : : * ignore nextval(), but treat all other functions normally.
671 : : */
672 : : bool
2865 673 : 126 : contain_volatile_functions_not_nextval(Node *clause)
674 : : {
675 : 126 : return contain_volatile_functions_not_nextval_walker(clause, NULL);
676 : : }
677 : :
678 : : static bool
679 : 32 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
680 : : {
1259 681 [ + + + + ]: 52 : return (func_id != F_NEXTVAL &&
2865 682 : 20 : func_volatile(func_id) == PROVOLATILE_VOLATILE);
683 : : }
684 : :
685 : : static bool
3737 simon@2ndQuadrant.co 686 : 156 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
687 : : {
688 [ - + ]: 156 : if (node == NULL)
3737 simon@2ndQuadrant.co 689 :UBC 0 : return false;
690 : : /* Check for volatile functions in node itself */
2865 tgl@sss.pgh.pa.us 691 [ + + ]:CBC 156 : if (check_functions_in_node(node,
692 : : contain_volatile_functions_not_nextval_checker,
693 : : context))
694 : 3 : return true;
695 : :
696 : : /*
697 : : * See notes in contain_mutable_functions_walker about why we treat
698 : : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
699 : : * SQLValueFunction is stable. Hence, none of them are of interest here.
700 : : * Also, since we're intentionally ignoring nextval(), presumably we
701 : : * should ignore NextValueExpr.
702 : : */
703 : :
704 : : /* Recurse to check arguments */
705 [ - + ]: 153 : if (IsA(node, Query))
706 : : {
707 : : /* Recurse into subselects */
2865 tgl@sss.pgh.pa.us 708 :UBC 0 : return query_tree_walker((Query *) node,
709 : : contain_volatile_functions_not_nextval_walker,
710 : : context, 0);
711 : : }
2865 tgl@sss.pgh.pa.us 712 :CBC 153 : return expression_tree_walker(node,
713 : : contain_volatile_functions_not_nextval_walker,
714 : : context);
715 : : }
716 : :
717 : :
718 : : /*****************************************************************************
719 : : * Check queries for parallel unsafe and/or restricted constructs
720 : : *****************************************************************************/
721 : :
722 : : /*
723 : : * max_parallel_hazard
724 : : * Find the worst parallel-hazard level in the given query
725 : : *
726 : : * Returns the worst function hazard property (the earliest in this list:
727 : : * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
728 : : * be found in the given parsetree. We use this to find out whether the query
729 : : * can be parallelized at all. The caller will also save the result in
730 : : * PlannerGlobal so as to short-circuit checks of portions of the querytree
731 : : * later, in the common case where everything is SAFE.
732 : : */
733 : : char
1117 akapila@postgresql.o 734 : 164538 : max_parallel_hazard(Query *parse)
735 : : {
736 : : max_parallel_hazard_context context;
737 : :
2795 tgl@sss.pgh.pa.us 738 : 164538 : context.max_hazard = PROPARALLEL_SAFE;
739 : 164538 : context.max_interesting = PROPARALLEL_UNSAFE;
2553 740 : 164538 : context.safe_param_ids = NIL;
2795 741 : 164538 : (void) max_parallel_hazard_walker((Node *) parse, &context);
742 : 164538 : return context.max_hazard;
743 : : }
744 : :
745 : : /*
746 : : * is_parallel_safe
747 : : * Detect whether the given expr contains only parallel-safe functions
748 : : *
749 : : * root->glob->maxParallelHazard must previously have been set to the
750 : : * result of max_parallel_hazard() on the whole query.
751 : : */
752 : : bool
753 : 1000722 : is_parallel_safe(PlannerInfo *root, Node *node)
754 : : {
755 : : max_parallel_hazard_context context;
756 : : PlannerInfo *proot;
757 : : ListCell *l;
758 : :
759 : : /*
760 : : * Even if the original querytree contained nothing unsafe, we need to
761 : : * search the expression if we have generated any PARAM_EXEC Params while
762 : : * planning, because those are parallel-restricted and there might be one
763 : : * in this expression. But otherwise we don't need to look.
764 : : */
2701 765 [ + + ]: 1000722 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
2344 rhaas@postgresql.org 766 [ + + ]: 615660 : root->glob->paramExecTypes == NIL)
2795 tgl@sss.pgh.pa.us 767 : 600263 : return true;
768 : : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
769 : 400459 : context.max_hazard = PROPARALLEL_SAFE;
770 : 400459 : context.max_interesting = PROPARALLEL_RESTRICTED;
2553 771 : 400459 : context.safe_param_ids = NIL;
772 : :
773 : : /*
774 : : * The params that refer to the same or parent query level are considered
775 : : * parallel-safe. The idea is that we compute such params at Gather or
776 : : * Gather Merge node and pass their value to workers.
777 : : */
2341 rhaas@postgresql.org 778 [ + + ]: 954455 : for (proot = root; proot != NULL; proot = proot->parent_root)
779 : : {
780 [ + + + + : 583730 : foreach(l, proot->init_plans)
+ + ]
781 : : {
782 : 29734 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
783 : :
1733 tgl@sss.pgh.pa.us 784 : 29734 : context.safe_param_ids = list_concat(context.safe_param_ids,
785 : 29734 : initsubplan->setParam);
786 : : }
787 : : }
788 : :
2795 789 : 400459 : return !max_parallel_hazard_walker(node, &context);
790 : : }
791 : :
792 : : /* core logic for all parallel-hazard checks */
793 : : static bool
794 : 685070 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
795 : : {
796 [ + + + - ]: 685070 : switch (proparallel)
797 : : {
798 : 557655 : case PROPARALLEL_SAFE:
799 : : /* nothing to see here, move along */
800 : 557655 : break;
801 : 84306 : case PROPARALLEL_RESTRICTED:
802 : : /* increase max_hazard to RESTRICTED */
803 [ - + ]: 84306 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
804 : 84306 : context->max_hazard = proparallel;
805 : : /* done if we are not expecting any unsafe functions */
806 [ + + ]: 84306 : if (context->max_interesting == proparallel)
807 : 44579 : return true;
808 : 39727 : break;
809 : 43109 : case PROPARALLEL_UNSAFE:
810 : 43109 : context->max_hazard = proparallel;
811 : : /* we're always done at the first unsafe construct */
812 : 43109 : return true;
2795 tgl@sss.pgh.pa.us 813 :UBC 0 : default:
814 [ # # ]: 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
815 : : break;
816 : : }
2795 tgl@sss.pgh.pa.us 817 :CBC 597382 : return false;
818 : : }
819 : :
820 : : /* check_functions_in_node callback */
821 : : static bool
822 : 628976 : max_parallel_hazard_checker(Oid func_id, void *context)
823 : : {
824 : 628976 : return max_parallel_hazard_test(func_parallel(func_id),
825 : : (max_parallel_hazard_context *) context);
826 : : }
827 : :
828 : : static bool
829 : 8936655 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
830 : : {
3133 rhaas@postgresql.org 831 [ + + ]: 8936655 : if (node == NULL)
832 : 2425261 : return false;
833 : :
834 : : /* Check for hazardous functions in node itself */
2795 tgl@sss.pgh.pa.us 835 [ + + ]: 6511394 : if (check_functions_in_node(node, max_parallel_hazard_checker,
836 : : context))
2865 837 : 55901 : return true;
838 : :
839 : : /*
840 : : * It should be OK to treat MinMaxExpr as parallel-safe, since btree
841 : : * opclass support functions are generally parallel-safe. XmlExpr is a
842 : : * bit more dubious but we can probably get away with it. We err on the
843 : : * side of caution by treating CoerceToDomain as parallel-restricted.
844 : : * (Note: in principle that's wrong because a domain constraint could
845 : : * contain a parallel-unsafe function; but useful constraints probably
846 : : * never would have such, and assuming they do would cripple use of
847 : : * parallel query in the presence of domain types.) SQLValueFunction
848 : : * should be safe in all cases. NextValueExpr is parallel-unsafe.
849 : : */
850 [ + + ]: 6455493 : if (IsA(node, CoerceToDomain))
851 : : {
2795 852 [ + + ]: 9431 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
3077 rhaas@postgresql.org 853 : 2798 : return true;
854 : : }
855 : :
2049 akapila@postgresql.o 856 [ + + ]: 6446062 : else if (IsA(node, NextValueExpr))
857 : : {
2466 tgl@sss.pgh.pa.us 858 [ + - ]: 223 : if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
859 : 223 : return true;
860 : : }
861 : :
862 : : /*
863 : : * Treat window functions as parallel-restricted because we aren't sure
864 : : * whether the input row ordering is fully deterministic, and the output
865 : : * of window functions might vary across workers if not. (In some cases,
866 : : * like where the window frame orders by a primary key, we could relax
867 : : * this restriction. But it doesn't currently seem worth expending extra
868 : : * effort to do so.)
869 : : */
2049 akapila@postgresql.o 870 [ + + ]: 6445839 : else if (IsA(node, WindowFunc))
871 : : {
872 [ + + ]: 2652 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
873 : 1178 : return true;
874 : : }
875 : :
876 : : /*
877 : : * As a notational convenience for callers, look through RestrictInfo.
878 : : */
2865 tgl@sss.pgh.pa.us 879 [ + + ]: 6443187 : else if (IsA(node, RestrictInfo))
880 : : {
3077 rhaas@postgresql.org 881 : 104478 : RestrictInfo *rinfo = (RestrictInfo *) node;
882 : :
2795 tgl@sss.pgh.pa.us 883 : 104478 : return max_parallel_hazard_walker((Node *) rinfo->clause, context);
884 : : }
885 : :
886 : : /*
887 : : * Really we should not see SubLink during a max_interesting == restricted
888 : : * scan, but if we do, return true.
889 : : */
2616 rhaas@postgresql.org 890 [ + + ]: 6338709 : else if (IsA(node, SubLink))
891 : : {
2795 tgl@sss.pgh.pa.us 892 [ - + ]: 15350 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
3133 rhaas@postgresql.org 893 :UBC 0 : return true;
894 : : }
895 : :
896 : : /*
897 : : * Only parallel-safe SubPlans can be sent to workers. Within the
898 : : * testexpr of the SubPlan, Params representing the output columns of the
899 : : * subplan can be treated as parallel-safe, so temporarily add their IDs
900 : : * to the safe_param_ids list while examining the testexpr.
901 : : */
2616 rhaas@postgresql.org 902 [ + + ]:CBC 6323359 : else if (IsA(node, SubPlan))
903 : : {
2553 tgl@sss.pgh.pa.us 904 : 12804 : SubPlan *subplan = (SubPlan *) node;
905 : : List *save_safe_param_ids;
906 : :
907 [ + + + - ]: 25455 : if (!subplan->parallel_safe &&
908 : 12651 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
909 : 12651 : return true;
910 : 153 : save_safe_param_ids = context->safe_param_ids;
1707 911 : 306 : context->safe_param_ids = list_concat_copy(context->safe_param_ids,
912 : 153 : subplan->paramIds);
2553 913 [ + + ]: 153 : if (max_parallel_hazard_walker(subplan->testexpr, context))
914 : 3 : return true; /* no need to restore safe_param_ids */
1733 915 : 150 : list_free(context->safe_param_ids);
2553 916 : 150 : context->safe_param_ids = save_safe_param_ids;
917 : : /* we must also check args, but no special Param treatment there */
918 [ - + ]: 150 : if (max_parallel_hazard_walker((Node *) subplan->args, context))
2553 tgl@sss.pgh.pa.us 919 :UBC 0 : return true;
920 : : /* don't want to recurse normally, so we're done */
2553 tgl@sss.pgh.pa.us 921 :CBC 150 : return false;
922 : : }
923 : :
924 : : /*
925 : : * We can't pass Params to workers at the moment either, so they are also
926 : : * parallel-restricted, unless they are PARAM_EXTERN Params or are
927 : : * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
928 : : * either generated within workers or can be computed by the leader and
929 : : * then their value can be passed to workers.
930 : : */
2865 931 [ + + ]: 6310555 : else if (IsA(node, Param))
932 : : {
2553 933 : 95308 : Param *param = (Param *) node;
934 : :
2361 rhaas@postgresql.org 935 [ + + ]: 95308 : if (param->paramkind == PARAM_EXTERN)
936 : 74301 : return false;
937 : :
2553 tgl@sss.pgh.pa.us 938 [ + + ]: 21007 : if (param->paramkind != PARAM_EXEC ||
939 [ + + ]: 20124 : !list_member_int(context->safe_param_ids, param->paramid))
940 : : {
941 [ + + ]: 15787 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
942 : 14937 : return true;
943 : : }
944 : 6070 : return false; /* nothing to recurse to */
945 : : }
946 : :
947 : : /*
948 : : * When we're first invoked on a completely unplanned tree, we must
949 : : * recurse into subqueries so to as to locate parallel-unsafe constructs
950 : : * anywhere in the tree.
951 : : */
2865 952 [ + + ]: 6215247 : else if (IsA(node, Query))
953 : : {
954 : 200162 : Query *query = (Query *) node;
955 : :
956 : : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
957 [ + + ]: 200162 : if (query->rowMarks != NULL)
958 : : {
2795 959 : 866 : context->max_hazard = PROPARALLEL_UNSAFE;
3133 rhaas@postgresql.org 960 : 866 : return true;
961 : : }
962 : :
963 : : /* Recurse into subselects */
2865 tgl@sss.pgh.pa.us 964 : 199296 : return query_tree_walker(query,
965 : : max_parallel_hazard_walker,
966 : : context, 0);
967 : : }
968 : :
969 : : /* Recurse to check arguments */
3133 rhaas@postgresql.org 970 : 6038542 : return expression_tree_walker(node,
971 : : max_parallel_hazard_walker,
972 : : context);
973 : : }
974 : :
975 : :
976 : : /*****************************************************************************
977 : : * Check clauses for nonstrict functions
978 : : *****************************************************************************/
979 : :
980 : : /*
981 : : * contain_nonstrict_functions
982 : : * Recursively search for nonstrict functions within a clause.
983 : : *
984 : : * Returns true if any nonstrict construct is found --- ie, anything that
985 : : * could produce non-NULL output with a NULL input.
986 : : *
987 : : * The idea here is that the caller has verified that the expression contains
988 : : * one or more Var or Param nodes (as appropriate for the caller's need), and
989 : : * now wishes to prove that the expression result will be NULL if any of these
990 : : * inputs is NULL. If we return false, then the proof succeeded.
991 : : */
992 : : bool
7805 tgl@sss.pgh.pa.us 993 : 840 : contain_nonstrict_functions(Node *clause)
994 : : {
995 : 840 : return contain_nonstrict_functions_walker(clause, NULL);
996 : : }
997 : :
998 : : static bool
2865 999 : 1131 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1000 : : {
1001 : 1131 : return !func_strict(func_id);
1002 : : }
1003 : :
1004 : : static bool
7805 1005 : 3599 : contain_nonstrict_functions_walker(Node *node, void *context)
1006 : : {
1007 [ - + ]: 3599 : if (node == NULL)
7805 tgl@sss.pgh.pa.us 1008 :UBC 0 : return false;
7400 tgl@sss.pgh.pa.us 1009 [ - + ]:CBC 3599 : if (IsA(node, Aggref))
1010 : : {
1011 : : /* an aggregate could return non-null with null input */
7400 tgl@sss.pgh.pa.us 1012 :UBC 0 : return true;
1013 : : }
2865 tgl@sss.pgh.pa.us 1014 [ - + ]:CBC 3599 : if (IsA(node, GroupingFunc))
1015 : : {
1016 : : /*
1017 : : * A GroupingFunc doesn't evaluate its arguments, and therefore must
1018 : : * be treated as nonstrict.
1019 : : */
2865 tgl@sss.pgh.pa.us 1020 :UBC 0 : return true;
1021 : : }
5586 tgl@sss.pgh.pa.us 1022 [ - + ]:CBC 3599 : if (IsA(node, WindowFunc))
1023 : : {
1024 : : /* a window function could return non-null with null input */
5586 tgl@sss.pgh.pa.us 1025 :UBC 0 : return true;
1026 : : }
1899 alvherre@alvh.no-ip. 1027 [ - + ]:CBC 3599 : if (IsA(node, SubscriptingRef))
1028 : : {
1222 tgl@sss.pgh.pa.us 1029 :UBC 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1030 : : const SubscriptRoutines *sbsroutines;
1031 : :
1032 : : /* Subscripting assignment is always presumed nonstrict */
1033 [ # # ]: 0 : if (sbsref->refassgnexpr != NULL)
1034 : 0 : return true;
1035 : : /* Otherwise we must look up the subscripting support methods */
1036 : 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
1220 1037 [ # # # # ]: 0 : if (!(sbsroutines && sbsroutines->fetch_strict))
1222 1038 : 0 : return true;
1039 : : /* else fall through to check args */
1040 : : }
7794 tgl@sss.pgh.pa.us 1041 [ - + ]:CBC 3599 : if (IsA(node, DistinctExpr))
1042 : : {
1043 : : /* IS DISTINCT FROM is inherently non-strict */
7794 tgl@sss.pgh.pa.us 1044 :UBC 0 : return true;
1045 : : }
4775 tgl@sss.pgh.pa.us 1046 [ - + ]:CBC 3599 : if (IsA(node, NullIfExpr))
1047 : : {
1048 : : /* NULLIF is inherently non-strict */
2865 tgl@sss.pgh.pa.us 1049 :UBC 0 : return true;
1050 : : }
7794 tgl@sss.pgh.pa.us 1051 [ - + ]:CBC 3599 : if (IsA(node, BoolExpr))
1052 : : {
7794 tgl@sss.pgh.pa.us 1053 :UBC 0 : BoolExpr *expr = (BoolExpr *) node;
1054 : :
1055 [ # # ]: 0 : switch (expr->boolop)
1056 : : {
7805 1057 : 0 : case AND_EXPR:
1058 : : case OR_EXPR:
1059 : : /* AND, OR are inherently non-strict */
1060 : 0 : return true;
1061 : 0 : default:
1062 : 0 : break;
1063 : : }
1064 : : }
7400 tgl@sss.pgh.pa.us 1065 [ - + ]:CBC 3599 : if (IsA(node, SubLink))
1066 : : {
1067 : : /* In some cases a sublink might be strict, but in general not */
7400 tgl@sss.pgh.pa.us 1068 :UBC 0 : return true;
1069 : : }
7400 tgl@sss.pgh.pa.us 1070 [ - + ]:CBC 3599 : if (IsA(node, SubPlan))
7400 tgl@sss.pgh.pa.us 1071 :UBC 0 : return true;
5714 tgl@sss.pgh.pa.us 1072 [ - + ]:CBC 3599 : if (IsA(node, AlternativeSubPlan))
5714 tgl@sss.pgh.pa.us 1073 :UBC 0 : return true;
7249 tgl@sss.pgh.pa.us 1074 [ - + ]:CBC 3599 : if (IsA(node, FieldStore))
7249 tgl@sss.pgh.pa.us 1075 :UBC 0 : return true;
1880 tgl@sss.pgh.pa.us 1076 [ + + ]:CBC 3599 : if (IsA(node, CoerceViaIO))
1077 : : {
1078 : : /*
1079 : : * CoerceViaIO is strict regardless of whether the I/O functions are,
1080 : : * so just go look at its argument; asking check_functions_in_node is
1081 : : * useless expense and could deliver the wrong answer.
1082 : : */
1083 : 529 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1084 : : context);
1085 : : }
2388 1086 [ - + ]: 3070 : if (IsA(node, ArrayCoerceExpr))
1087 : : {
1088 : : /*
1089 : : * ArrayCoerceExpr is strict at the array level, regardless of what
1090 : : * the per-element expression is; so we should ignore elemexpr and
1091 : : * recurse only into the arg.
1092 : : */
1880 tgl@sss.pgh.pa.us 1093 :UBC 0 : return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
1094 : : context);
1095 : : }
7805 tgl@sss.pgh.pa.us 1096 [ + + ]:CBC 3070 : if (IsA(node, CaseExpr))
1097 : 86 : return true;
6723 1098 [ - + ]: 2984 : if (IsA(node, ArrayExpr))
6723 tgl@sss.pgh.pa.us 1099 :UBC 0 : return true;
7279 tgl@sss.pgh.pa.us 1100 [ - + ]:CBC 2984 : if (IsA(node, RowExpr))
7279 tgl@sss.pgh.pa.us 1101 :UBC 0 : return true;
6682 tgl@sss.pgh.pa.us 1102 [ - + ]:CBC 2984 : if (IsA(node, RowCompareExpr))
6682 tgl@sss.pgh.pa.us 1103 :UBC 0 : return true;
7728 tgl@sss.pgh.pa.us 1104 [ - + ]:CBC 2984 : if (IsA(node, CoalesceExpr))
7728 tgl@sss.pgh.pa.us 1105 :UBC 0 : return true;
6867 tgl@sss.pgh.pa.us 1106 [ - + ]:CBC 2984 : if (IsA(node, MinMaxExpr))
6867 tgl@sss.pgh.pa.us 1107 :UBC 0 : return true;
6321 tgl@sss.pgh.pa.us 1108 [ - + ]:CBC 2984 : if (IsA(node, XmlExpr))
6321 tgl@sss.pgh.pa.us 1109 :UBC 0 : return true;
7805 tgl@sss.pgh.pa.us 1110 [ - + ]:CBC 2984 : if (IsA(node, NullTest))
7805 tgl@sss.pgh.pa.us 1111 :UBC 0 : return true;
7805 tgl@sss.pgh.pa.us 1112 [ - + ]:CBC 2984 : if (IsA(node, BooleanTest))
7805 tgl@sss.pgh.pa.us 1113 :UBC 0 : return true;
1114 : :
1115 : : /* Check other function-containing nodes */
2388 tgl@sss.pgh.pa.us 1116 [ - + ]:CBC 2984 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1117 : : context))
2865 tgl@sss.pgh.pa.us 1118 :LBC (3) : return true;
1119 : :
7805 tgl@sss.pgh.pa.us 1120 :CBC 2984 : return expression_tree_walker(node, contain_nonstrict_functions_walker,
1121 : : context);
1122 : : }
1123 : :
1124 : : /*****************************************************************************
1125 : : * Check clauses for Params
1126 : : *****************************************************************************/
1127 : :
1128 : : /*
1129 : : * contain_exec_param
1130 : : * Recursively search for PARAM_EXEC Params within a clause.
1131 : : *
1132 : : * Returns true if the clause contains any PARAM_EXEC Param with a paramid
1133 : : * appearing in the given list of Param IDs. Does not descend into
1134 : : * subqueries!
1135 : : */
1136 : : bool
1339 1137 : 1373 : contain_exec_param(Node *clause, List *param_ids)
1138 : : {
1139 : 1373 : return contain_exec_param_walker(clause, param_ids);
1140 : : }
1141 : :
1142 : : static bool
1143 : 1478 : contain_exec_param_walker(Node *node, List *param_ids)
1144 : : {
1145 [ + + ]: 1478 : if (node == NULL)
1146 : 9 : return false;
1147 [ + + ]: 1469 : if (IsA(node, Param))
1148 : : {
1149 : 6 : Param *p = (Param *) node;
1150 : :
1151 [ + - + - ]: 12 : if (p->paramkind == PARAM_EXEC &&
1152 : 6 : list_member_int(param_ids, p->paramid))
1153 : 6 : return true;
1154 : : }
1155 : 1463 : return expression_tree_walker(node, contain_exec_param_walker, param_ids);
1156 : : }
1157 : :
1158 : : /*****************************************************************************
1159 : : * Check clauses for context-dependent nodes
1160 : : *****************************************************************************/
1161 : :
1162 : : /*
1163 : : * contain_context_dependent_node
1164 : : * Recursively search for context-dependent nodes within a clause.
1165 : : *
1166 : : * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
1167 : : * not nested within another one, or they'll see the wrong test value. If one
1168 : : * appears "bare" in the arguments of a SQL function, then we can't inline the
1169 : : * SQL function for fear of creating such a situation. The same applies for
1170 : : * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
1171 : : *
1172 : : * CoerceToDomainValue would have the same issue if domain CHECK expressions
1173 : : * could get inlined into larger expressions, but presently that's impossible.
1174 : : * Still, it might be allowed in future, or other node types with similar
1175 : : * issues might get invented. So give this function a generic name, and set
1176 : : * up the recursion state to allow multiple flag bits.
1177 : : */
1178 : : static bool
2806 1179 : 9772 : contain_context_dependent_node(Node *clause)
1180 : : {
1181 : 9772 : int flags = 0;
1182 : :
1183 : 9772 : return contain_context_dependent_node_walker(clause, &flags);
1184 : : }
1185 : :
1186 : : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1187 : :
1188 : : static bool
1189 : 20910 : contain_context_dependent_node_walker(Node *node, int *flags)
1190 : : {
1191 [ + + ]: 20910 : if (node == NULL)
1192 : 4344 : return false;
1193 [ + + ]: 16566 : if (IsA(node, CaseTestExpr))
1993 1194 : 3 : return !(*flags & CCDN_CASETESTEXPR_OK);
1195 [ - + ]: 16563 : else if (IsA(node, CaseExpr))
1196 : : {
2806 tgl@sss.pgh.pa.us 1197 :UBC 0 : CaseExpr *caseexpr = (CaseExpr *) node;
1198 : :
1199 : : /*
1200 : : * If this CASE doesn't have a test expression, then it doesn't create
1201 : : * a context in which CaseTestExprs should appear, so just fall
1202 : : * through and treat it as a generic expression node.
1203 : : */
1204 [ # # ]: 0 : if (caseexpr->arg)
1205 : : {
1206 : 0 : int save_flags = *flags;
1207 : : bool res;
1208 : :
1209 : : /*
1210 : : * Note: in principle, we could distinguish the various sub-parts
1211 : : * of a CASE construct and set the flag bit only for some of them,
1212 : : * since we are only expecting CaseTestExprs to appear in the
1213 : : * "expr" subtree of the CaseWhen nodes. But it doesn't really
1214 : : * seem worth any extra code. If there are any bare CaseTestExprs
1215 : : * elsewhere in the CASE, something's wrong already.
1216 : : */
1993 1217 : 0 : *flags |= CCDN_CASETESTEXPR_OK;
2806 1218 : 0 : res = expression_tree_walker(node,
1219 : : contain_context_dependent_node_walker,
1220 : : (void *) flags);
1221 : 0 : *flags = save_flags;
1222 : 0 : return res;
1223 : : }
1224 : : }
1993 tgl@sss.pgh.pa.us 1225 [ - + ]:CBC 16563 : else if (IsA(node, ArrayCoerceExpr))
1226 : : {
1993 tgl@sss.pgh.pa.us 1227 :UBC 0 : ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
1228 : : int save_flags;
1229 : : bool res;
1230 : :
1231 : : /* Check the array expression */
1232 [ # # ]: 0 : if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
1233 : 0 : return true;
1234 : :
1235 : : /* Check the elemexpr, which is allowed to contain CaseTestExpr */
1236 : 0 : save_flags = *flags;
1237 : 0 : *flags |= CCDN_CASETESTEXPR_OK;
1238 : 0 : res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
1239 : : flags);
1240 : 0 : *flags = save_flags;
1241 : 0 : return res;
1242 : : }
2806 tgl@sss.pgh.pa.us 1243 :CBC 16563 : return expression_tree_walker(node, contain_context_dependent_node_walker,
1244 : : (void *) flags);
1245 : : }
1246 : :
1247 : : /*****************************************************************************
1248 : : * Check clauses for Vars passed to non-leakproof functions
1249 : : *****************************************************************************/
1250 : :
1251 : : /*
1252 : : * contain_leaked_vars
1253 : : * Recursively scan a clause to discover whether it contains any Var
1254 : : * nodes (of the current query level) that are passed as arguments to
1255 : : * leaky functions.
1256 : : *
1257 : : * Returns true if the clause contains any non-leakproof functions that are
1258 : : * passed Var nodes of the current query level, and which might therefore leak
1259 : : * data. Such clauses must be applied after any lower-level security barrier
1260 : : * clauses.
1261 : : */
1262 : : bool
3275 sfrost@snowman.net 1263 : 2308 : contain_leaked_vars(Node *clause)
1264 : : {
1265 : 2308 : return contain_leaked_vars_walker(clause, NULL);
1266 : : }
1267 : :
1268 : : static bool
2865 tgl@sss.pgh.pa.us 1269 : 2375 : contain_leaked_vars_checker(Oid func_id, void *context)
1270 : : {
1271 : 2375 : return !get_func_leakproof(func_id);
1272 : : }
1273 : :
1274 : : static bool
3275 sfrost@snowman.net 1275 : 4727 : contain_leaked_vars_walker(Node *node, void *context)
1276 : : {
4444 rhaas@postgresql.org 1277 [ - + ]: 4727 : if (node == NULL)
4444 rhaas@postgresql.org 1278 :UBC 0 : return false;
1279 : :
4444 rhaas@postgresql.org 1280 [ + + - - :CBC 4727 : switch (nodeTag(node))
- + + ]
1281 : : {
1282 : 2325 : case T_Var:
1283 : : case T_Const:
1284 : : case T_Param:
1285 : : case T_ArrayExpr:
1286 : : case T_FieldSelect:
1287 : : case T_FieldStore:
1288 : : case T_NamedArgExpr:
1289 : : case T_BoolExpr:
1290 : : case T_RelabelType:
1291 : : case T_CollateExpr:
1292 : : case T_CaseExpr:
1293 : : case T_CaseTestExpr:
1294 : : case T_RowExpr:
1295 : : case T_SQLValueFunction:
1296 : : case T_NullTest:
1297 : : case T_BooleanTest:
1298 : : case T_NextValueExpr:
1299 : : case T_List:
1300 : :
1301 : : /*
1302 : : * We know these node types don't contain function calls; but
1303 : : * something further down in the node tree might.
1304 : : */
1305 : 2325 : break;
1306 : :
1307 : 2375 : case T_FuncExpr:
1308 : : case T_OpExpr:
1309 : : case T_DistinctExpr:
1310 : : case T_NullIfExpr:
1311 : : case T_ScalarArrayOpExpr:
1312 : : case T_CoerceViaIO:
1313 : : case T_ArrayCoerceExpr:
1314 : :
1315 : : /*
1316 : : * If node contains a leaky function call, and there's any Var
1317 : : * underneath it, reject.
1318 : : */
2865 tgl@sss.pgh.pa.us 1319 [ + + ]: 2375 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1320 [ + + ]: 1108 : context) &&
1321 : 1108 : contain_var_clause(node))
1322 : 1080 : return true;
4444 rhaas@postgresql.org 1323 : 1295 : break;
1324 : :
1223 tgl@sss.pgh.pa.us 1325 :UBC 0 : case T_SubscriptingRef:
1326 : : {
1327 : 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1328 : : const SubscriptRoutines *sbsroutines;
1329 : :
1330 : : /* Consult the subscripting support method info */
1222 1331 : 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
1332 : : NULL);
1220 1333 [ # # ]: 0 : if (!sbsroutines ||
1334 [ # # ]: 0 : !(sbsref->refassgnexpr != NULL ?
1222 1335 [ # # ]: 0 : sbsroutines->store_leakproof :
1336 [ # # ]: 0 : sbsroutines->fetch_leakproof))
1337 : : {
1338 : : /* Node is leaky, so reject if it contains Vars */
1223 1339 [ # # ]: 0 : if (contain_var_clause(node))
1340 : 0 : return true;
1341 : : }
1342 : : }
1343 : 0 : break;
1344 : :
4444 rhaas@postgresql.org 1345 : 0 : case T_RowCompareExpr:
1346 : : {
1347 : : /*
1348 : : * It's worth special-casing this because a leaky comparison
1349 : : * function only compromises one pair of row elements, which
1350 : : * might not contain Vars while others do.
1351 : : */
1352 : 0 : RowCompareExpr *rcexpr = (RowCompareExpr *) node;
1353 : : ListCell *opid;
1354 : : ListCell *larg;
1355 : : ListCell *rarg;
1356 : :
3275 sfrost@snowman.net 1357 [ # # # # : 0 : forthree(opid, rcexpr->opnos,
# # # # #
# # # # #
# # # # #
# ]
1358 : : larg, rcexpr->largs,
1359 : : rarg, rcexpr->rargs)
1360 : : {
4326 bruce@momjian.us 1361 : 0 : Oid funcid = get_opcode(lfirst_oid(opid));
1362 : :
3275 sfrost@snowman.net 1363 [ # # # # ]: 0 : if (!get_func_leakproof(funcid) &&
1364 [ # # ]: 0 : (contain_var_clause((Node *) lfirst(larg)) ||
1365 : 0 : contain_var_clause((Node *) lfirst(rarg))))
4444 rhaas@postgresql.org 1366 : 0 : return true;
1367 : : }
1368 : : }
1369 : 0 : break;
1370 : :
1929 tgl@sss.pgh.pa.us 1371 : 0 : case T_MinMaxExpr:
1372 : : {
1373 : : /*
1374 : : * MinMaxExpr is leakproof if the comparison function it calls
1375 : : * is leakproof.
1376 : : */
1377 : 0 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
1378 : : TypeCacheEntry *typentry;
1379 : : bool leakproof;
1380 : :
1381 : : /* Look up the btree comparison function for the datatype */
1382 : 0 : typentry = lookup_type_cache(minmaxexpr->minmaxtype,
1383 : : TYPECACHE_CMP_PROC);
1384 [ # # ]: 0 : if (OidIsValid(typentry->cmp_proc))
1385 : 0 : leakproof = get_func_leakproof(typentry->cmp_proc);
1386 : : else
1387 : : {
1388 : : /*
1389 : : * The executor will throw an error, but here we just
1390 : : * treat the missing function as leaky.
1391 : : */
1392 : 0 : leakproof = false;
1393 : : }
1394 : :
1395 [ # # # # ]: 0 : if (!leakproof &&
1396 : 0 : contain_var_clause((Node *) minmaxexpr->args))
1397 : 0 : return true;
1398 : : }
1399 : 0 : break;
1400 : :
3187 mail@joeconway.com 1401 :CBC 15 : case T_CurrentOfExpr:
1402 : :
1403 : : /*
1404 : : * WHERE CURRENT OF doesn't contain leaky function calls.
1405 : : * Moreover, it is essential that this is considered non-leaky,
1406 : : * since the planner must always generate a TID scan when CURRENT
1407 : : * OF is present -- cf. cost_tidscan.
1408 : : */
1409 : 15 : return false;
1410 : :
4444 rhaas@postgresql.org 1411 : 12 : default:
1412 : :
1413 : : /*
1414 : : * If we don't recognize the node tag, assume it might be leaky.
1415 : : * This prevents an unexpected security hole if someone adds a new
1416 : : * node type that can call a function.
1417 : : */
1418 : 12 : return true;
1419 : : }
3275 sfrost@snowman.net 1420 : 3620 : return expression_tree_walker(node, contain_leaked_vars_walker,
1421 : : context);
1422 : : }
1423 : :
1424 : : /*
1425 : : * find_nonnullable_rels
1426 : : * Determine which base rels are forced nonnullable by given clause.
1427 : : *
1428 : : * Returns the set of all Relids that are referenced in the clause in such
1429 : : * a way that the clause cannot possibly return TRUE if any of these Relids
1430 : : * is an all-NULL row. (It is OK to err on the side of conservatism; hence
1431 : : * the analysis here is simplistic.)
1432 : : *
1433 : : * The semantics here are subtly different from contain_nonstrict_functions:
1434 : : * that function is concerned with NULL results from arbitrary expressions,
1435 : : * but here we assume that the input is a Boolean expression, and wish to
1436 : : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1437 : : * the expression to have been AND/OR flattened and converted to implicit-AND
1438 : : * format.
1439 : : *
1440 : : * Note: this function is largely duplicative of find_nonnullable_vars().
1441 : : * The reason not to simplify this function into a thin wrapper around
1442 : : * find_nonnullable_vars() is that the tested conditions really are different:
1443 : : * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
1444 : : * that either v1 or v2 can't be NULL, but it does prove that the t1 row
1445 : : * as a whole can't be all-NULL. Also, the behavior for PHVs is different.
1446 : : *
1447 : : * top_level is true while scanning top-level AND/OR structure; here, showing
1448 : : * the result is either FALSE or NULL is good enough. top_level is false when
1449 : : * we have descended below a NOT or a strict function: now we must be able to
1450 : : * prove that the subexpression goes to NULL.
1451 : : *
1452 : : * We don't use expression_tree_walker here because we don't want to descend
1453 : : * through very many kinds of nodes; only the ones we can be sure are strict.
1454 : : */
1455 : : Relids
6690 tgl@sss.pgh.pa.us 1456 : 46738 : find_nonnullable_rels(Node *clause)
1457 : : {
1458 : 46738 : return find_nonnullable_rels_walker(clause, true);
1459 : : }
1460 : :
1461 : : static Relids
1462 : 296021 : find_nonnullable_rels_walker(Node *node, bool top_level)
1463 : : {
1464 : 296021 : Relids result = NULL;
1465 : : ListCell *l;
1466 : :
1467 [ + + ]: 296021 : if (node == NULL)
1468 : 2696 : return NULL;
1469 [ + + ]: 293325 : if (IsA(node, Var))
1470 : : {
1471 : 96339 : Var *var = (Var *) node;
1472 : :
1473 [ + - ]: 96339 : if (var->varlevelsup == 0)
1474 : 96339 : result = bms_make_singleton(var->varno);
1475 : : }
1476 [ + + ]: 196986 : else if (IsA(node, List))
1477 : : {
1478 : : /*
1479 : : * At top level, we are examining an implicit-AND list: if any of the
1480 : : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1481 : : * not at top level, we are examining the arguments of a strict
1482 : : * function: if any of them produce NULL then the result of the
1483 : : * function must be NULL. So in both cases, the set of nonnullable
1484 : : * rels is the union of those found in the arms, and we pass down the
1485 : : * top_level flag unmodified.
1486 : : */
1487 [ + - + + : 287823 : foreach(l, (List *) node)
+ + ]
1488 : : {
1489 : 182342 : result = bms_join(result,
1490 : 182342 : find_nonnullable_rels_walker(lfirst(l),
1491 : : top_level));
1492 : : }
1493 : : }
1494 [ + + ]: 91505 : else if (IsA(node, FuncExpr))
1495 : : {
1496 : 2879 : FuncExpr *expr = (FuncExpr *) node;
1497 : :
1498 [ + + ]: 2879 : if (func_strict(expr->funcid))
1499 : 2795 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1500 : : }
1501 [ + + ]: 88626 : else if (IsA(node, OpExpr))
1502 : : {
1503 : 53834 : OpExpr *expr = (OpExpr *) node;
1504 : :
5988 1505 : 53834 : set_opfuncid(expr);
1506 [ + - ]: 53834 : if (func_strict(expr->opfuncid))
6690 1507 : 53834 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1508 : : }
1509 [ + + ]: 34792 : else if (IsA(node, ScalarArrayOpExpr))
1510 : : {
1511 : 3719 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1512 : :
6642 1513 [ + - ]: 3719 : if (is_strict_saop(expr, true))
6690 1514 : 3719 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1515 : : }
1516 [ + + ]: 31073 : else if (IsA(node, BoolExpr))
1517 : : {
1518 : 2647 : BoolExpr *expr = (BoolExpr *) node;
1519 : :
6267 1520 [ + + + - ]: 2647 : switch (expr->boolop)
1521 : : {
1522 : 200 : case AND_EXPR:
1523 : : /* At top level we can just recurse (to the List case) */
1524 [ + - ]: 200 : if (top_level)
1525 : : {
1526 : 200 : result = find_nonnullable_rels_walker((Node *) expr->args,
1527 : : top_level);
1528 : 200 : break;
1529 : : }
1530 : :
1531 : : /*
1532 : : * Below top level, even if one arm produces NULL, the result
1533 : : * could be FALSE (hence not NULL). However, if *all* the
1534 : : * arms produce NULL then the result is NULL, so we can take
1535 : : * the intersection of the sets of nonnullable rels, just as
1536 : : * for OR. Fall through to share code.
1537 : : */
1538 : : /* FALL THRU */
1539 : : case OR_EXPR:
1540 : :
1541 : : /*
1542 : : * OR is strict if all of its arms are, so we can take the
1543 : : * intersection of the sets of nonnullable rels for each arm.
1544 : : * This works for both values of top_level.
1545 : : */
1546 [ + - + + : 3417 : foreach(l, expr->args)
+ + ]
1547 : : {
1548 : : Relids subresult;
1549 : :
1550 : 3082 : subresult = find_nonnullable_rels_walker(lfirst(l),
1551 : : top_level);
5995 bruce@momjian.us 1552 [ + + ]: 3082 : if (result == NULL) /* first subresult? */
6267 tgl@sss.pgh.pa.us 1553 : 1556 : result = subresult;
1554 : : else
1555 : 1526 : result = bms_int_members(result, subresult);
1556 : :
1557 : : /*
1558 : : * If the intersection is empty, we can stop looking. This
1559 : : * also justifies the test for first-subresult above.
1560 : : */
1561 [ + + ]: 3082 : if (bms_is_empty(result))
1562 : 1221 : break;
1563 : : }
1564 : 1556 : break;
1565 : 891 : case NOT_EXPR:
1566 : : /* NOT will return null if its arg is null */
1567 : 891 : result = find_nonnullable_rels_walker((Node *) expr->args,
1568 : : false);
1569 : 891 : break;
6267 tgl@sss.pgh.pa.us 1570 :UBC 0 : default:
1571 [ # # ]: 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1572 : : break;
1573 : : }
1574 : : }
6690 tgl@sss.pgh.pa.us 1575 [ + + ]:CBC 28426 : else if (IsA(node, RelabelType))
1576 : : {
1577 : 754 : RelabelType *expr = (RelabelType *) node;
1578 : :
1579 : 754 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1580 : : }
6158 1581 [ + + ]: 27672 : else if (IsA(node, CoerceViaIO))
1582 : : {
1583 : : /* not clear this is useful, but it can't hurt */
1584 : 69 : CoerceViaIO *expr = (CoerceViaIO *) node;
1585 : :
1586 : 69 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1587 : : }
6228 1588 [ - + ]: 27603 : else if (IsA(node, ArrayCoerceExpr))
1589 : : {
1590 : : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
6228 tgl@sss.pgh.pa.us 1591 :UBC 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1592 : :
1593 : 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1594 : : }
6690 tgl@sss.pgh.pa.us 1595 [ - + ]:CBC 27603 : else if (IsA(node, ConvertRowtypeExpr))
1596 : : {
1597 : : /* not clear this is useful, but it can't hurt */
6690 tgl@sss.pgh.pa.us 1598 :UBC 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1599 : :
1600 : 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1601 : : }
4783 tgl@sss.pgh.pa.us 1602 [ - + ]:CBC 27603 : else if (IsA(node, CollateExpr))
1603 : : {
4783 tgl@sss.pgh.pa.us 1604 :UBC 0 : CollateExpr *expr = (CollateExpr *) node;
1605 : :
1606 : 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1607 : : }
6690 tgl@sss.pgh.pa.us 1608 [ + + ]:CBC 27603 : else if (IsA(node, NullTest))
1609 : : {
1610 : : /* IS NOT NULL can be considered strict, but only at top level */
1611 : 2119 : NullTest *expr = (NullTest *) node;
1612 : :
5217 1613 [ + + + + : 2119 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
+ + ]
6690 1614 : 1318 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1615 : : }
1616 [ + + ]: 25484 : else if (IsA(node, BooleanTest))
1617 : : {
1618 : : /* Boolean tests that reject NULL are strict at top level */
1619 : 35 : BooleanTest *expr = (BooleanTest *) node;
1620 : :
1621 [ + - ]: 35 : if (top_level &&
1622 [ + - ]: 35 : (expr->booltesttype == IS_TRUE ||
1623 [ + + ]: 35 : expr->booltesttype == IS_FALSE ||
1624 [ - + ]: 3 : expr->booltesttype == IS_NOT_UNKNOWN))
1625 : 32 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1626 : : }
526 1627 [ + + ]: 25449 : else if (IsA(node, SubPlan))
1628 : : {
1629 : 49 : SubPlan *splan = (SubPlan *) node;
1630 : :
1631 : : /*
1632 : : * For some types of SubPlan, we can infer strictness from Vars in the
1633 : : * testexpr (the LHS of the original SubLink).
1634 : : *
1635 : : * For ANY_SUBLINK, if the subquery produces zero rows, the result is
1636 : : * always FALSE. If the subquery produces more than one row, the
1637 : : * per-row results of the testexpr are combined using OR semantics.
1638 : : * Hence ANY_SUBLINK can be strict only at top level, but there it's
1639 : : * as strict as the testexpr is.
1640 : : *
1641 : : * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
1642 : : * result is always NULL. Otherwise, the result is as strict as the
1643 : : * testexpr is. So we can check regardless of top_level.
1644 : : *
1645 : : * We can't prove anything for other sublink types (in particular,
1646 : : * note that ALL_SUBLINK will return TRUE if the subquery is empty).
1647 : : */
1648 [ + + + + ]: 49 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1649 [ - + ]: 34 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1650 : 15 : result = find_nonnullable_rels_walker(splan->testexpr, top_level);
1651 : : }
5654 1652 [ + + ]: 25400 : else if (IsA(node, PlaceHolderVar))
1653 : : {
1654 : 232 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1655 : :
1656 : : /*
1657 : : * If the contained expression forces any rels non-nullable, so does
1658 : : * the PHV.
1659 : : */
1660 : 232 : result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
1661 : :
1662 : : /*
1663 : : * If the PHV's syntactic scope is exactly one rel, it will be forced
1664 : : * to be evaluated at that rel, and so it will behave like a Var of
1665 : : * that rel: if the rel's entire output goes to null, so will the PHV.
1666 : : * (If the syntactic scope is a join, we know that the PHV will go to
1667 : : * null if the whole join does; but that is AND semantics while we
1668 : : * need OR semantics for find_nonnullable_rels' result, so we can't do
1669 : : * anything with the knowledge.)
1670 : : */
1903 1671 [ + - + + ]: 464 : if (phv->phlevelsup == 0 &&
1672 : 232 : bms_membership(phv->phrels) == BMS_SINGLETON)
1673 : 139 : result = bms_add_members(result, phv->phrels);
1674 : : }
5722 1675 : 293325 : return result;
1676 : : }
1677 : :
1678 : : /*
1679 : : * find_nonnullable_vars
1680 : : * Determine which Vars are forced nonnullable by given clause.
1681 : : *
1682 : : * Returns the set of all level-zero Vars that are referenced in the clause in
1683 : : * such a way that the clause cannot possibly return TRUE if any of these Vars
1684 : : * is NULL. (It is OK to err on the side of conservatism; hence the analysis
1685 : : * here is simplistic.)
1686 : : *
1687 : : * The semantics here are subtly different from contain_nonstrict_functions:
1688 : : * that function is concerned with NULL results from arbitrary expressions,
1689 : : * but here we assume that the input is a Boolean expression, and wish to
1690 : : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1691 : : * the expression to have been AND/OR flattened and converted to implicit-AND
1692 : : * format.
1693 : : *
1694 : : * Attnos of the identified Vars are returned in a multibitmapset (a List of
1695 : : * Bitmapsets). List indexes correspond to relids (varnos), while the per-rel
1696 : : * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
1697 : : *
1698 : : * top_level is true while scanning top-level AND/OR structure; here, showing
1699 : : * the result is either FALSE or NULL is good enough. top_level is false when
1700 : : * we have descended below a NOT or a strict function: now we must be able to
1701 : : * prove that the subexpression goes to NULL.
1702 : : *
1703 : : * We don't use expression_tree_walker here because we don't want to descend
1704 : : * through very many kinds of nodes; only the ones we can be sure are strict.
1705 : : */
1706 : : List *
1707 : 21118 : find_nonnullable_vars(Node *clause)
1708 : : {
1709 : 21118 : return find_nonnullable_vars_walker(clause, true);
1710 : : }
1711 : :
1712 : : static List *
1713 : 134750 : find_nonnullable_vars_walker(Node *node, bool top_level)
1714 : : {
1715 : 134750 : List *result = NIL;
1716 : : ListCell *l;
1717 : :
1718 [ + + ]: 134750 : if (node == NULL)
1719 : 250 : return NIL;
1720 [ + + ]: 134500 : if (IsA(node, Var))
1721 : : {
1722 : 50671 : Var *var = (Var *) node;
1723 : :
1724 [ + - ]: 50671 : if (var->varlevelsup == 0)
515 1725 : 50671 : result = mbms_add_member(result,
1726 : : var->varno,
1727 : 50671 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1728 : : }
5722 1729 [ + + ]: 83829 : else if (IsA(node, List))
1730 : : {
1731 : : /*
1732 : : * At top level, we are examining an implicit-AND list: if any of the
1733 : : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1734 : : * not at top level, we are examining the arguments of a strict
1735 : : * function: if any of them produce NULL then the result of the
1736 : : * function must be NULL. So in both cases, the set of nonnullable
1737 : : * vars is the union of those found in the arms, and we pass down the
1738 : : * top_level flag unmodified.
1739 : : */
1740 [ + - + + : 133834 : foreach(l, (List *) node)
+ + ]
1741 : : {
515 1742 : 84872 : result = mbms_add_members(result,
1743 : 84872 : find_nonnullable_vars_walker(lfirst(l),
1744 : : top_level));
1745 : : }
1746 : : }
5722 1747 [ + + ]: 34867 : else if (IsA(node, FuncExpr))
1748 : : {
1749 : 182 : FuncExpr *expr = (FuncExpr *) node;
1750 : :
1751 [ + - ]: 182 : if (func_strict(expr->funcid))
1752 : 182 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1753 : : }
1754 [ + + ]: 34685 : else if (IsA(node, OpExpr))
1755 : : {
1756 : 27149 : OpExpr *expr = (OpExpr *) node;
1757 : :
1758 : 27149 : set_opfuncid(expr);
1759 [ + - ]: 27149 : if (func_strict(expr->opfuncid))
1760 : 27149 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1761 : : }
1762 [ + + ]: 7536 : else if (IsA(node, ScalarArrayOpExpr))
1763 : : {
1764 : 738 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1765 : :
1766 [ + - ]: 738 : if (is_strict_saop(expr, true))
1767 : 738 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1768 : : }
1769 [ + + ]: 6798 : else if (IsA(node, BoolExpr))
1770 : : {
1771 : 167 : BoolExpr *expr = (BoolExpr *) node;
1772 : :
1773 [ - + + - ]: 167 : switch (expr->boolop)
1774 : : {
5722 tgl@sss.pgh.pa.us 1775 :UBC 0 : case AND_EXPR:
1776 : :
1777 : : /*
1778 : : * At top level we can just recurse (to the List case), since
1779 : : * the result should be the union of what we can prove in each
1780 : : * arm.
1781 : : */
1782 [ # # ]: 0 : if (top_level)
1783 : : {
1784 : 0 : result = find_nonnullable_vars_walker((Node *) expr->args,
1785 : : top_level);
1786 : 0 : break;
1787 : : }
1788 : :
1789 : : /*
1790 : : * Below top level, even if one arm produces NULL, the result
1791 : : * could be FALSE (hence not NULL). However, if *all* the
1792 : : * arms produce NULL then the result is NULL, so we can take
1793 : : * the intersection of the sets of nonnullable vars, just as
1794 : : * for OR. Fall through to share code.
1795 : : */
1796 : : /* FALL THRU */
1797 : : case OR_EXPR:
1798 : :
1799 : : /*
1800 : : * OR is strict if all of its arms are, so we can take the
1801 : : * intersection of the sets of nonnullable vars for each arm.
1802 : : * This works for both values of top_level.
1803 : : */
5722 tgl@sss.pgh.pa.us 1804 [ + - + + :CBC 362 : foreach(l, expr->args)
+ + ]
1805 : : {
1806 : : List *subresult;
1807 : :
1808 : 296 : subresult = find_nonnullable_vars_walker(lfirst(l),
1809 : : top_level);
1810 [ + + ]: 296 : if (result == NIL) /* first subresult? */
1811 : 142 : result = subresult;
1812 : : else
515 1813 : 154 : result = mbms_int_members(result, subresult);
1814 : :
1815 : : /*
1816 : : * If the intersection is empty, we can stop looking. This
1817 : : * also justifies the test for first-subresult above.
1818 : : */
5722 1819 [ + + ]: 296 : if (result == NIL)
1820 : 76 : break;
1821 : : }
1822 : 142 : break;
1823 : 25 : case NOT_EXPR:
1824 : : /* NOT will return null if its arg is null */
1825 : 25 : result = find_nonnullable_vars_walker((Node *) expr->args,
1826 : : false);
1827 : 25 : break;
5722 tgl@sss.pgh.pa.us 1828 :UBC 0 : default:
1829 [ # # ]: 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1830 : : break;
1831 : : }
1832 : : }
5722 tgl@sss.pgh.pa.us 1833 [ + + ]:CBC 6631 : else if (IsA(node, RelabelType))
1834 : : {
1835 : 265 : RelabelType *expr = (RelabelType *) node;
1836 : :
1837 : 265 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1838 : : }
1839 [ + + ]: 6366 : else if (IsA(node, CoerceViaIO))
1840 : : {
1841 : : /* not clear this is useful, but it can't hurt */
1842 : 27 : CoerceViaIO *expr = (CoerceViaIO *) node;
1843 : :
1844 : 27 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1845 : : }
1846 [ - + ]: 6339 : else if (IsA(node, ArrayCoerceExpr))
1847 : : {
1848 : : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
5722 tgl@sss.pgh.pa.us 1849 :UBC 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1850 : :
1851 : 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1852 : : }
5722 tgl@sss.pgh.pa.us 1853 [ - + ]:CBC 6339 : else if (IsA(node, ConvertRowtypeExpr))
1854 : : {
1855 : : /* not clear this is useful, but it can't hurt */
5722 tgl@sss.pgh.pa.us 1856 :UBC 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1857 : :
1858 : 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1859 : : }
4783 tgl@sss.pgh.pa.us 1860 [ - + ]:CBC 6339 : else if (IsA(node, CollateExpr))
1861 : : {
4783 tgl@sss.pgh.pa.us 1862 :UBC 0 : CollateExpr *expr = (CollateExpr *) node;
1863 : :
1864 : 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1865 : : }
5722 tgl@sss.pgh.pa.us 1866 [ + + ]:CBC 6339 : else if (IsA(node, NullTest))
1867 : : {
1868 : : /* IS NOT NULL can be considered strict, but only at top level */
1869 : 127 : NullTest *expr = (NullTest *) node;
1870 : :
5217 1871 [ + - + + : 127 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
+ - ]
5722 1872 : 45 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1873 : : }
1874 [ - + ]: 6212 : else if (IsA(node, BooleanTest))
1875 : : {
1876 : : /* Boolean tests that reject NULL are strict at top level */
5722 tgl@sss.pgh.pa.us 1877 :UBC 0 : BooleanTest *expr = (BooleanTest *) node;
1878 : :
1879 [ # # ]: 0 : if (top_level &&
1880 [ # # ]: 0 : (expr->booltesttype == IS_TRUE ||
1881 [ # # ]: 0 : expr->booltesttype == IS_FALSE ||
1882 [ # # ]: 0 : expr->booltesttype == IS_NOT_UNKNOWN))
1883 : 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1884 : : }
526 tgl@sss.pgh.pa.us 1885 [ + + ]:CBC 6212 : else if (IsA(node, SubPlan))
1886 : : {
526 tgl@sss.pgh.pa.us 1887 :GBC 6 : SubPlan *splan = (SubPlan *) node;
1888 : :
1889 : : /* See analysis in find_nonnullable_rels_walker */
1890 [ + - - + ]: 6 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
526 tgl@sss.pgh.pa.us 1891 [ # # ]:UBC 0 : splan->subLinkType == ROWCOMPARE_SUBLINK)
526 tgl@sss.pgh.pa.us 1892 :GBC 6 : result = find_nonnullable_vars_walker(splan->testexpr, top_level);
1893 : : }
5654 tgl@sss.pgh.pa.us 1894 [ + + ]:CBC 6206 : else if (IsA(node, PlaceHolderVar))
1895 : : {
1896 : 27 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1897 : :
1898 : 27 : result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
1899 : : }
6690 1900 : 134500 : return result;
1901 : : }
1902 : :
1903 : : /*
1904 : : * find_forced_null_vars
1905 : : * Determine which Vars must be NULL for the given clause to return TRUE.
1906 : : *
1907 : : * This is the complement of find_nonnullable_vars: find the level-zero Vars
1908 : : * that must be NULL for the clause to return TRUE. (It is OK to err on the
1909 : : * side of conservatism; hence the analysis here is simplistic. In fact,
1910 : : * we only detect simple "var IS NULL" tests at the top level.)
1911 : : *
1912 : : * As with find_nonnullable_vars, we return the varattnos of the identified
1913 : : * Vars in a multibitmapset.
1914 : : */
1915 : : List *
5722 1916 : 54115 : find_forced_null_vars(Node *node)
1917 : : {
1918 : 54115 : List *result = NIL;
1919 : : Var *var;
1920 : : ListCell *l;
1921 : :
1922 [ + + ]: 54115 : if (node == NULL)
1923 : 2410 : return NIL;
1924 : : /* Check single-clause cases using subroutine */
1925 : 51705 : var = find_forced_null_var(node);
1926 [ + + ]: 51705 : if (var)
1927 : : {
515 1928 : 579 : result = mbms_add_member(result,
1929 : : var->varno,
1930 : 579 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1931 : : }
1932 : : /* Otherwise, handle AND-conditions */
5722 1933 [ + + ]: 51126 : else if (IsA(node, List))
1934 : : {
1935 : : /*
1936 : : * At top level, we are examining an implicit-AND list: if any of the
1937 : : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
1938 : : */
1939 [ + - + + : 51705 : foreach(l, (List *) node)
+ + ]
1940 : : {
515 1941 : 30660 : result = mbms_add_members(result,
1942 : 30660 : find_forced_null_vars((Node *) lfirst(l)));
1943 : : }
1944 : : }
5722 1945 [ + + ]: 30081 : else if (IsA(node, BoolExpr))
1946 : : {
1947 : 2048 : BoolExpr *expr = (BoolExpr *) node;
1948 : :
1949 : : /*
1950 : : * We don't bother considering the OR case, because it's fairly
1951 : : * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
1952 : : * the NOT case isn't worth expending code on.
1953 : : */
1954 [ - + ]: 2048 : if (expr->boolop == AND_EXPR)
1955 : : {
1956 : : /* At top level we can just recurse (to the List case) */
5722 tgl@sss.pgh.pa.us 1957 :UBC 0 : result = find_forced_null_vars((Node *) expr->args);
1958 : : }
1959 : : }
5722 tgl@sss.pgh.pa.us 1960 :CBC 51705 : return result;
1961 : : }
1962 : :
1963 : : /*
1964 : : * find_forced_null_var
1965 : : * Return the Var forced null by the given clause, or NULL if it's
1966 : : * not an IS NULL-type clause. For success, the clause must enforce
1967 : : * *only* nullness of the particular Var, not any other conditions.
1968 : : *
1969 : : * This is just the single-clause case of find_forced_null_vars(), without
1970 : : * any allowance for AND conditions. It's used by initsplan.c on individual
1971 : : * qual clauses. The reason for not just applying find_forced_null_vars()
1972 : : * is that if an AND of an IS NULL clause with something else were to somehow
1973 : : * survive AND/OR flattening, initsplan.c might get fooled into discarding
1974 : : * the whole clause when only the IS NULL part of it had been proved redundant.
1975 : : */
1976 : : Var *
1977 : 252108 : find_forced_null_var(Node *node)
1978 : : {
1979 [ - + ]: 252108 : if (node == NULL)
5722 tgl@sss.pgh.pa.us 1980 :UBC 0 : return NULL;
5722 tgl@sss.pgh.pa.us 1981 [ + + ]:CBC 252108 : if (IsA(node, NullTest))
1982 : : {
1983 : : /* check for var IS NULL */
1984 : 5496 : NullTest *expr = (NullTest *) node;
1985 : :
5217 1986 [ + + + + ]: 5496 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
1987 : : {
5421 bruce@momjian.us 1988 : 1825 : Var *var = (Var *) expr->arg;
1989 : :
5722 tgl@sss.pgh.pa.us 1990 [ + - + + ]: 1825 : if (var && IsA(var, Var) &&
1991 [ + - ]: 1768 : var->varlevelsup == 0)
1992 : 1768 : return var;
1993 : : }
1994 : : }
1995 [ + + ]: 246612 : else if (IsA(node, BooleanTest))
1996 : : {
1997 : : /* var IS UNKNOWN is equivalent to var IS NULL */
1998 : 262 : BooleanTest *expr = (BooleanTest *) node;
1999 : :
2000 [ + + ]: 262 : if (expr->booltesttype == IS_UNKNOWN)
2001 : : {
5421 bruce@momjian.us 2002 : 21 : Var *var = (Var *) expr->arg;
2003 : :
5722 tgl@sss.pgh.pa.us 2004 [ + - + - ]: 21 : if (var && IsA(var, Var) &&
2005 [ + - ]: 21 : var->varlevelsup == 0)
2006 : 21 : return var;
2007 : : }
2008 : : }
2009 : 250319 : return NULL;
2010 : : }
2011 : :
2012 : : /*
2013 : : * Can we treat a ScalarArrayOpExpr as strict?
2014 : : *
2015 : : * If "falseOK" is true, then a "false" result can be considered strict,
2016 : : * else we need to guarantee an actual NULL result for NULL input.
2017 : : *
2018 : : * "foo op ALL array" is strict if the op is strict *and* we can prove
2019 : : * that the array input isn't an empty array. We can check that
2020 : : * for the cases of an array constant and an ARRAY[] construct.
2021 : : *
2022 : : * "foo op ANY array" is strict in the falseOK sense if the op is strict.
2023 : : * If not falseOK, the test is the same as for "foo op ALL array".
2024 : : */
2025 : : static bool
6642 2026 : 4457 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2027 : : {
2028 : : Node *rightop;
2029 : :
2030 : : /* The contained operator must be strict. */
5988 2031 : 4457 : set_sa_opfuncid(expr);
2032 [ - + ]: 4457 : if (!func_strict(expr->opfuncid))
6642 tgl@sss.pgh.pa.us 2033 :UBC 0 : return false;
2034 : : /* If ANY and falseOK, that's all we need to check. */
6642 tgl@sss.pgh.pa.us 2035 [ + + + - ]:CBC 4457 : if (expr->useOr && falseOK)
2036 : 4419 : return true;
2037 : : /* Else, we have to see if the array is provably non-empty. */
2038 [ - + ]: 38 : Assert(list_length(expr->args) == 2);
2039 : 38 : rightop = (Node *) lsecond(expr->args);
2040 [ + - + - ]: 38 : if (rightop && IsA(rightop, Const))
6642 tgl@sss.pgh.pa.us 2041 :UBC 0 : {
6642 tgl@sss.pgh.pa.us 2042 :CBC 38 : Datum arraydatum = ((Const *) rightop)->constvalue;
2043 : 38 : bool arrayisnull = ((Const *) rightop)->constisnull;
2044 : : ArrayType *arrayval;
2045 : : int nitems;
2046 : :
2047 [ - + ]: 38 : if (arrayisnull)
6642 tgl@sss.pgh.pa.us 2048 :UBC 0 : return false;
6642 tgl@sss.pgh.pa.us 2049 :CBC 38 : arrayval = DatumGetArrayTypeP(arraydatum);
2050 : 38 : nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
2051 [ + - ]: 38 : if (nitems > 0)
2052 : 38 : return true;
2053 : : }
6642 tgl@sss.pgh.pa.us 2054 [ # # # # ]:UBC 0 : else if (rightop && IsA(rightop, ArrayExpr))
2055 : : {
2056 : 0 : ArrayExpr *arrayexpr = (ArrayExpr *) rightop;
2057 : :
2058 [ # # # # ]: 0 : if (arrayexpr->elements != NIL && !arrayexpr->multidims)
2059 : 0 : return true;
2060 : : }
2061 : 0 : return false;
2062 : : }
2063 : :
2064 : :
2065 : : /*****************************************************************************
2066 : : * Check for "pseudo-constant" clauses
2067 : : *****************************************************************************/
2068 : :
2069 : : /*
2070 : : * is_pseudo_constant_clause
2071 : : * Detect whether an expression is "pseudo constant", ie, it contains no
2072 : : * variables of the current query level and no uses of volatile functions.
2073 : : * Such an expr is not necessarily a true constant: it can still contain
2074 : : * Params and outer-level Vars, not to mention functions whose results
2075 : : * may vary from one statement to the next. However, the expr's value
2076 : : * will be constant over any one scan of the current query, so it can be
2077 : : * used as, eg, an indexscan key. (Actually, the condition for indexscan
2078 : : * keys is weaker than this; see is_pseudo_constant_for_index().)
2079 : : *
2080 : : * CAUTION: this function omits to test for one very important class of
2081 : : * not-constant expressions, namely aggregates (Aggrefs). In current usage
2082 : : * this is only applied to WHERE clauses and so a check for Aggrefs would be
2083 : : * a waste of cycles; but be sure to also check contain_agg_clause() if you
2084 : : * want to know about pseudo-constness in other contexts. The same goes
2085 : : * for window functions (WindowFuncs).
2086 : : */
2087 : : bool
8645 tgl@sss.pgh.pa.us 2088 :CBC 2394 : is_pseudo_constant_clause(Node *clause)
2089 : : {
2090 : : /*
2091 : : * We could implement this check in one recursive scan. But since the
2092 : : * check for volatile functions is both moderately expensive and unlikely
2093 : : * to fail, it seems better to look for Vars first and only check for
2094 : : * volatile functions if we find no Vars.
2095 : : */
2096 [ + - ]: 2394 : if (!contain_var_clause(clause) &&
8045 2097 [ + - ]: 2394 : !contain_volatile_functions(clause))
8645 2098 : 2394 : return true;
8645 tgl@sss.pgh.pa.us 2099 :UBC 0 : return false;
2100 : : }
2101 : :
2102 : : /*
2103 : : * is_pseudo_constant_clause_relids
2104 : : * Same as above, except caller already has available the var membership
2105 : : * of the expression; this lets us avoid the contain_var_clause() scan.
2106 : : */
2107 : : bool
7411 tgl@sss.pgh.pa.us 2108 :CBC 176267 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2109 : : {
2110 [ + + ]: 176267 : if (bms_is_empty(relids) &&
2111 [ + - ]: 173000 : !contain_volatile_functions(clause))
2112 : 173000 : return true;
2113 : 3267 : return false;
2114 : : }
2115 : :
2116 : :
2117 : : /*****************************************************************************
2118 : : * *
2119 : : * General clause-manipulating routines *
2120 : : * *
2121 : : *****************************************************************************/
2122 : :
2123 : : /*
2124 : : * NumRelids
2125 : : * (formerly clause_relids)
2126 : : *
2127 : : * Returns the number of different base relations referenced in 'clause'.
2128 : : */
2129 : : int
1179 2130 : 840 : NumRelids(PlannerInfo *root, Node *clause)
2131 : : {
2132 : : int result;
2133 : 840 : Relids varnos = pull_varnos(root, clause);
2134 : :
440 2135 : 840 : varnos = bms_del_members(varnos, root->outer_join_rels);
2136 : 840 : result = bms_num_members(varnos);
7736 2137 : 840 : bms_free(varnos);
9015 2138 : 840 : return result;
2139 : : }
2140 : :
2141 : : /*
2142 : : * CommuteOpExpr: commute a binary operator clause
2143 : : *
2144 : : * XXX the clause is destructively modified!
2145 : : */
2146 : : void
6654 2147 : 8289 : CommuteOpExpr(OpExpr *clause)
2148 : : {
2149 : : Oid opoid;
2150 : : Node *temp;
2151 : :
2152 : : /* Sanity checks: caller is at fault if these fail */
7794 2153 [ + - - + ]: 16578 : if (!is_opclause(clause) ||
7259 neilc@samurai.com 2154 : 8289 : list_length(clause->args) != 2)
7569 tgl@sss.pgh.pa.us 2155 [ # # ]:UBC 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2156 : :
7794 tgl@sss.pgh.pa.us 2157 :CBC 8289 : opoid = get_commutator(clause->opno);
2158 : :
2159 [ - + ]: 8289 : if (!OidIsValid(opoid))
7569 tgl@sss.pgh.pa.us 2160 [ # # ]:UBC 0 : elog(ERROR, "could not find commutator for operator %u",
2161 : : clause->opno);
2162 : :
2163 : : /*
2164 : : * modify the clause in-place!
2165 : : */
7794 tgl@sss.pgh.pa.us 2166 :CBC 8289 : clause->opno = opoid;
2167 : 8289 : clause->opfuncid = InvalidOid;
2168 : : /* opresulttype, opretset, opcollid, inputcollid need not change */
2169 : :
7263 neilc@samurai.com 2170 : 8289 : temp = linitial(clause->args);
2171 : 8289 : linitial(clause->args) = lsecond(clause->args);
9012 tgl@sss.pgh.pa.us 2172 : 8289 : lsecond(clause->args) = temp;
9716 bruce@momjian.us 2173 : 8289 : }
2174 : :
2175 : : /*
2176 : : * Helper for eval_const_expressions: check that datatype of an attribute
2177 : : * is still what it was when the expression was parsed. This is needed to
2178 : : * guard against improper simplification after ALTER COLUMN TYPE. (XXX we
2179 : : * may well need to make similar checks elsewhere?)
2180 : : *
2181 : : * rowtypeid may come from a whole-row Var, and therefore it can be a domain
2182 : : * over composite, but for this purpose we only care about checking the type
2183 : : * of a contained field.
2184 : : */
2185 : : static bool
7180 tgl@sss.pgh.pa.us 2186 : 263 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
2187 : : Oid expectedtype, int32 expectedtypmod,
2188 : : Oid expectedcollation)
2189 : : {
2190 : : TupleDesc tupdesc;
2191 : : Form_pg_attribute attr;
2192 : :
2193 : : /* No issue for RECORD, since there is no way to ALTER such a type */
2194 [ + + ]: 263 : if (rowtypeid == RECORDOID)
2195 : 21 : return true;
2362 2196 : 242 : tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
7180 2197 [ + - - + ]: 242 : if (fieldnum <= 0 || fieldnum > tupdesc->natts)
2198 : : {
6512 tgl@sss.pgh.pa.us 2199 [ # # ]:UBC 0 : ReleaseTupleDesc(tupdesc);
7180 2200 : 0 : return false;
2201 : : }
2429 andres@anarazel.de 2202 :CBC 242 : attr = TupleDescAttr(tupdesc, fieldnum - 1);
7180 tgl@sss.pgh.pa.us 2203 [ + - ]: 242 : if (attr->attisdropped ||
2204 [ + - ]: 242 : attr->atttypid != expectedtype ||
4814 peter_e@gmx.net 2205 [ + - ]: 242 : attr->atttypmod != expectedtypmod ||
2206 [ - + ]: 242 : attr->attcollation != expectedcollation)
2207 : : {
6512 tgl@sss.pgh.pa.us 2208 [ # # ]:UBC 0 : ReleaseTupleDesc(tupdesc);
7180 2209 : 0 : return false;
2210 : : }
6512 tgl@sss.pgh.pa.us 2211 [ + - ]:CBC 242 : ReleaseTupleDesc(tupdesc);
7180 2212 : 242 : return true;
2213 : : }
2214 : :
2215 : :
2216 : : /*--------------------
2217 : : * eval_const_expressions
2218 : : *
2219 : : * Reduce any recognizably constant subexpressions of the given
2220 : : * expression tree, for example "2 + 2" => "4". More interestingly,
2221 : : * we can reduce certain boolean expressions even when they contain
2222 : : * non-constant subexpressions: "x OR true" => "true" no matter what
2223 : : * the subexpression x is. (XXX We assume that no such subexpression
2224 : : * will have important side-effects, which is not necessarily a good
2225 : : * assumption in the presence of user-defined functions; do we need a
2226 : : * pg_proc flag that prevents discarding the execution of a function?)
2227 : : *
2228 : : * We do understand that certain functions may deliver non-constant
2229 : : * results even with constant inputs, "nextval()" being the classic
2230 : : * example. Functions that are not marked "immutable" in pg_proc
2231 : : * will not be pre-evaluated here, although we will reduce their
2232 : : * arguments as far as possible.
2233 : : *
2234 : : * Whenever a function is eliminated from the expression by means of
2235 : : * constant-expression evaluation or inlining, we add the function to
2236 : : * root->glob->invalItems. This ensures the plan is known to depend on
2237 : : * such functions, even though they aren't referenced anymore.
2238 : : *
2239 : : * We assume that the tree has already been type-checked and contains
2240 : : * only operators and functions that are reasonable to try to execute.
2241 : : *
2242 : : * NOTE: "root" can be passed as NULL if the caller never wants to do any
2243 : : * Param substitutions nor receive info about inlined functions.
2244 : : *
2245 : : * NOTE: the planner assumes that this will always flatten nested AND and
2246 : : * OR clauses into N-argument form. See comments in prepqual.c.
2247 : : *
2248 : : * NOTE: another critical effect is that any function calls that require
2249 : : * default arguments will be expanded, and named-argument calls will be
2250 : : * converted to positional notation. The executor won't handle either.
2251 : : *--------------------
2252 : : */
2253 : : Node *
5857 2254 : 550336 : eval_const_expressions(PlannerInfo *root, Node *node)
2255 : : {
2256 : : eval_const_expressions_context context;
2257 : :
2258 [ + + ]: 550336 : if (root)
2259 : 431358 : context.boundParams = root->glob->boundParams; /* bound Params */
2260 : : else
2261 : 118978 : context.boundParams = NULL;
4607 2262 : 550336 : context.root = root; /* for inlined-function dependencies */
7247 2263 : 550336 : context.active_fns = NIL; /* nothing being recursively simplified */
7011 2264 : 550336 : context.case_val = NULL; /* no CASE being examined */
7247 2265 : 550336 : context.estimate = false; /* safe transformations only */
2266 : 550336 : return eval_const_expressions_mutator(node, &context);
2267 : : }
2268 : :
2269 : : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
2270 : : /*--------------------
2271 : : * convert_saop_to_hashed_saop
2272 : : *
2273 : : * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
2274 : : * function for any ScalarArrayOpExpr that looks like it would be useful to
2275 : : * evaluate using a hash table rather than a linear search.
2276 : : *
2277 : : * We'll use a hash table if all of the following conditions are met:
2278 : : * 1. The 2nd argument of the array contain only Consts.
2279 : : * 2. useOr is true or there is a valid negator operator for the
2280 : : * ScalarArrayOpExpr's opno.
2281 : : * 3. There's valid hash function for both left and righthand operands and
2282 : : * these hash functions are the same.
2283 : : * 4. If the array contains enough elements for us to consider it to be
2284 : : * worthwhile using a hash table rather than a linear search.
2285 : : */
2286 : : void
1102 drowley@postgresql.o 2287 : 379729 : convert_saop_to_hashed_saop(Node *node)
2288 : : {
2289 : 379729 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2290 : 379729 : }
2291 : :
2292 : : static bool
2293 : 2657232 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2294 : : {
2295 [ + + ]: 2657232 : if (node == NULL)
2296 : 64953 : return false;
2297 : :
2298 [ + + ]: 2592279 : if (IsA(node, ScalarArrayOpExpr))
2299 : : {
2300 : 12651 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2301 : 12651 : Expr *arrayarg = (Expr *) lsecond(saop->args);
2302 : : Oid lefthashfunc;
2303 : : Oid righthashfunc;
2304 : :
1012 2305 [ + - + + ]: 12651 : if (arrayarg && IsA(arrayarg, Const) &&
2306 [ + + ]: 6197 : !((Const *) arrayarg)->constisnull)
2307 : : {
2308 [ + + ]: 6188 : if (saop->useOr)
2309 : : {
2310 [ + + ]: 5453 : if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
2311 [ + - ]: 5309 : lefthashfunc == righthashfunc)
2312 : : {
2313 : 5309 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2314 : 5309 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2315 : : int nitems;
2316 : :
2317 : : /*
2318 : : * Only fill in the hash functions if the array looks
2319 : : * large enough for it to be worth hashing instead of
2320 : : * doing a linear search.
2321 : : */
2322 : 5309 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2323 : :
2324 [ + + ]: 5309 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2325 : : {
2326 : : /* Looks good. Fill in the hash functions */
2327 : 102 : saop->hashfuncid = lefthashfunc;
2328 : : }
2329 : 5995 : return true;
2330 : : }
2331 : : }
2332 : : else /* !saop->useOr */
2333 : : {
2334 : 735 : Oid negator = get_negator(saop->opno);
2335 : :
2336 : : /*
2337 : : * Check if this is a NOT IN using an operator whose negator
2338 : : * is hashable. If so we can still build a hash table and
2339 : : * just ensure the lookup items are not in the hash table.
2340 : : */
2341 [ + - + + ]: 1470 : if (OidIsValid(negator) &&
2342 : 735 : get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
2343 [ + - ]: 686 : lefthashfunc == righthashfunc)
2344 : : {
2345 : 686 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2346 : 686 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2347 : : int nitems;
2348 : :
2349 : : /*
2350 : : * Only fill in the hash functions if the array looks
2351 : : * large enough for it to be worth hashing instead of
2352 : : * doing a linear search.
2353 : : */
2354 : 686 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2355 : :
2356 [ + + ]: 686 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2357 : : {
2358 : : /* Looks good. Fill in the hash functions */
2359 : 35 : saop->hashfuncid = lefthashfunc;
2360 : :
2361 : : /*
2362 : : * Also set the negfuncid. The executor will need
2363 : : * that to perform hashtable lookups.
2364 : : */
2365 : 35 : saop->negfuncid = get_opcode(negator);
2366 : : }
2367 : 686 : return true;
2368 : : }
2369 : : }
2370 : : }
2371 : : }
2372 : :
1102 2373 : 2586284 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2374 : : }
2375 : :
2376 : :
2377 : : /*--------------------
2378 : : * estimate_expression_value
2379 : : *
2380 : : * This function attempts to estimate the value of an expression for
2381 : : * planning purposes. It is in essence a more aggressive version of
2382 : : * eval_const_expressions(): we will perform constant reductions that are
2383 : : * not necessarily 100% safe, but are reasonable for estimation purposes.
2384 : : *
2385 : : * Currently the extra steps that are taken in this mode are:
2386 : : * 1. Substitute values for Params, where a bound Param value has been made
2387 : : * available by the caller of planner(), even if the Param isn't marked
2388 : : * constant. This effectively means that we plan using the first supplied
2389 : : * value of the Param.
2390 : : * 2. Fold stable, as well as immutable, functions to constants.
2391 : : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2392 : : *--------------------
2393 : : */
2394 : : Node *
6264 tgl@sss.pgh.pa.us 2395 : 343971 : estimate_expression_value(PlannerInfo *root, Node *node)
2396 : : {
2397 : : eval_const_expressions_context context;
2398 : :
2489 2399 : 343971 : context.boundParams = root->glob->boundParams; /* bound Params */
2400 : : /* we do not need to mark the plan as depending on inlined functions */
4607 2401 : 343971 : context.root = NULL;
7247 2402 : 343971 : context.active_fns = NIL; /* nothing being recursively simplified */
7011 2403 : 343971 : context.case_val = NULL; /* no CASE being examined */
7247 2404 : 343971 : context.estimate = true; /* unsafe transformations OK */
2405 : 343971 : return eval_const_expressions_mutator(node, &context);
2406 : : }
2407 : :
2408 : : /*
2409 : : * The generic case in eval_const_expressions_mutator is to recurse using
2410 : : * expression_tree_mutator, which will copy the given node unchanged but
2411 : : * const-simplify its arguments (if any) as far as possible. If the node
2412 : : * itself does immutable processing, and each of its arguments were reduced
2413 : : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2414 : : * node types need more complicated logic; for example, a CASE expression
2415 : : * might be reducible to a constant even if not all its subtrees are.)
2416 : : */
2417 : : #define ece_generic_processing(node) \
2418 : : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2419 : : (void *) context)
2420 : :
2421 : : /*
2422 : : * Check whether all arguments of the given node were reduced to Consts.
2423 : : * By going directly to expression_tree_walker, contain_non_const_walker
2424 : : * is not applied to the node itself, only to its children.
2425 : : */
2426 : : #define ece_all_arguments_const(node) \
2427 : : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2428 : :
2429 : : /* Generic macro for applying evaluate_expr */
2430 : : #define ece_evaluate_expr(node) \
2431 : : ((Node *) evaluate_expr((Expr *) (node), \
2432 : : exprType((Node *) (node)), \
2433 : : exprTypmod((Node *) (node)), \
2434 : : exprCollation((Node *) (node))))
2435 : :
2436 : : /*
2437 : : * Recursive guts of eval_const_expressions/estimate_expression_value
2438 : : */
2439 : : static Node *
2440 : 3925741 : eval_const_expressions_mutator(Node *node,
2441 : : eval_const_expressions_context *context)
2442 : : {
2443 : :
2444 : : /* since this function recurses, it could be driven to stack overflow */
58 akorotkov@postgresql 2445 : 3925741 : check_stack_depth();
2446 : :
8967 tgl@sss.pgh.pa.us 2447 [ + + ]: 3925741 : if (node == NULL)
2448 : 174582 : return NULL;
4521 2449 [ + + + + : 3751159 : switch (nodeTag(node))
+ + + + +
+ + + + +
+ + + + +
+ + + + +
+ + ]
2450 : : {
2451 : 119450 : case T_Param:
2452 : : {
bruce@momjian.us 2453 : 119450 : Param *param = (Param *) node;
2306 tgl@sss.pgh.pa.us 2454 : 119450 : ParamListInfo paramLI = context->boundParams;
2455 : :
2456 : : /* Look to see if we've been given a value for this Param */
4521 bruce@momjian.us 2457 [ + + + + ]: 119450 : if (param->paramkind == PARAM_EXTERN &&
2306 tgl@sss.pgh.pa.us 2458 : 16962 : paramLI != NULL &&
4521 bruce@momjian.us 2459 [ + - ]: 16962 : param->paramid > 0 &&
2306 tgl@sss.pgh.pa.us 2460 [ + - ]: 16962 : param->paramid <= paramLI->numParams)
2461 : : {
2462 : : ParamExternData *prm;
2463 : : ParamExternData prmdata;
2464 : :
2465 : : /*
2466 : : * Give hook a chance in case parameter is dynamic. Tell
2467 : : * it that this fetch is speculative, so it should avoid
2468 : : * erroring out if parameter is unavailable.
2469 : : */
2470 [ + + ]: 16962 : if (paramLI->paramFetch != NULL)
2471 : 3508 : prm = paramLI->paramFetch(paramLI, param->paramid,
2472 : : true, &prmdata);
2473 : : else
2474 : 13454 : prm = ¶mLI->params[param->paramid - 1];
2475 : :
2476 : : /*
2477 : : * We don't just check OidIsValid, but insist that the
2478 : : * fetched type match the Param, just in case the hook did
2479 : : * something unexpected. No need to throw an error here
2480 : : * though; leave that for runtime.
2481 : : */
2089 2482 [ + - ]: 16962 : if (OidIsValid(prm->ptype) &&
2483 [ + + ]: 16962 : prm->ptype == param->paramtype)
2484 : : {
2485 : : /* OK to substitute parameter value? */
4521 2486 [ + + ]: 16961 : if (context->estimate ||
2487 [ + + ]: 16958 : (prm->pflags & PARAM_FLAG_CONST))
2488 : : {
2489 : : /*
2490 : : * Return a Const representing the param value.
2491 : : * Must copy pass-by-ref datatypes, since the
2492 : : * Param might be in a memory context
2493 : : * shorter-lived than our output plan should be.
2494 : : */
2495 : : int16 typLen;
2496 : : bool typByVal;
2497 : : Datum pval;
2498 : : Const *con;
2499 : :
2500 : 16958 : get_typlenbyval(param->paramtype,
2501 : : &typLen, &typByVal);
bruce@momjian.us 2502 [ + + + + ]: 16958 : if (prm->isnull || typByVal)
2503 : 11027 : pval = prm->value;
2504 : : else
2505 : 5931 : pval = datumCopy(prm->value, typByVal, typLen);
1005 tgl@sss.pgh.pa.us 2506 : 16958 : con = makeConst(param->paramtype,
2507 : : param->paramtypmod,
2508 : : param->paramcollid,
2509 : : (int) typLen,
2510 : : pval,
2511 : 16958 : prm->isnull,
2512 : : typByVal);
2513 : 16958 : con->location = param->location;
2514 : 16958 : return (Node *) con;
2515 : : }
2516 : : }
2517 : : }
2518 : :
2519 : : /*
2520 : : * Not replaceable, so just copy the Param (no need to
2521 : : * recurse)
2522 : : */
4521 bruce@momjian.us 2523 : 102492 : return (Node *) copyObject(param);
2524 : : }
3812 tgl@sss.pgh.pa.us 2525 : 1645 : case T_WindowFunc:
2526 : : {
2527 : 1645 : WindowFunc *expr = (WindowFunc *) node;
2528 : 1645 : Oid funcid = expr->winfnoid;
2529 : : List *args;
2530 : : Expr *aggfilter;
2531 : : HeapTuple func_tuple;
2532 : : WindowFunc *newexpr;
2533 : :
2534 : : /*
2535 : : * We can't really simplify a WindowFunc node, but we mustn't
2536 : : * just fall through to the default processing, because we
2537 : : * have to apply expand_function_arguments to its argument
2538 : : * list. That takes care of inserting default arguments and
2539 : : * expanding named-argument notation.
2540 : : */
2541 : 1645 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2542 [ - + ]: 1645 : if (!HeapTupleIsValid(func_tuple))
3812 tgl@sss.pgh.pa.us 2543 [ # # ]:UBC 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2544 : :
1039 tgl@sss.pgh.pa.us 2545 :CBC 1645 : args = expand_function_arguments(expr->args,
2546 : : false, expr->wintype,
2547 : : func_tuple);
2548 : :
3812 2549 : 1645 : ReleaseSysCache(func_tuple);
2550 : :
2551 : : /* Now, recursively simplify the args (which are a List) */
2552 : : args = (List *)
2553 : 1645 : expression_tree_mutator((Node *) args,
2554 : : eval_const_expressions_mutator,
2555 : : (void *) context);
2556 : : /* ... and the filter expression, which isn't */
2557 : : aggfilter = (Expr *)
2558 : 1645 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2559 : : context);
2560 : :
2561 : : /* And build the replacement WindowFunc node */
2562 : 1645 : newexpr = makeNode(WindowFunc);
2563 : 1645 : newexpr->winfnoid = expr->winfnoid;
2564 : 1645 : newexpr->wintype = expr->wintype;
2565 : 1645 : newexpr->wincollid = expr->wincollid;
2566 : 1645 : newexpr->inputcollid = expr->inputcollid;
2567 : 1645 : newexpr->args = args;
2568 : 1645 : newexpr->aggfilter = aggfilter;
2569 : 1645 : newexpr->winref = expr->winref;
2570 : 1645 : newexpr->winstar = expr->winstar;
2571 : 1645 : newexpr->winagg = expr->winagg;
2572 : 1645 : newexpr->location = expr->location;
2573 : :
2574 : 1645 : return (Node *) newexpr;
2575 : : }
4521 2576 : 261537 : case T_FuncExpr:
2577 : : {
bruce@momjian.us 2578 : 261537 : FuncExpr *expr = (FuncExpr *) node;
4405 tgl@sss.pgh.pa.us 2579 : 261537 : List *args = expr->args;
2580 : : Expr *simple;
2581 : : FuncExpr *newexpr;
2582 : :
2583 : : /*
2584 : : * Code for op/func reduction is pretty bulky, so split it out
2585 : : * as a separate function. Note: exprTypmod normally returns
2586 : : * -1 for a FuncExpr, but not when the node is recognizably a
2587 : : * length coercion; we want to preserve the typmod in the
2588 : : * eventual Const if so.
2589 : : */
2590 : 261537 : simple = simplify_function(expr->funcid,
2591 : : expr->funcresulttype,
2592 : : exprTypmod(node),
2593 : : expr->funccollid,
2594 : : expr->inputcollid,
2595 : : &args,
4101 2596 : 261537 : expr->funcvariadic,
2597 : : true,
2598 : : true,
2599 : : context);
4521 bruce@momjian.us 2600 [ + + ]: 260247 : if (simple) /* successfully simplified it */
2601 : 84611 : return (Node *) simple;
2602 : :
2603 : : /*
2604 : : * The expression cannot be simplified any further, so build
2605 : : * and return a replacement FuncExpr node using the
2606 : : * possibly-simplified arguments. Note that we have also
2607 : : * converted the argument list to positional notation.
2608 : : */
2609 : 175636 : newexpr = makeNode(FuncExpr);
2610 : 175636 : newexpr->funcid = expr->funcid;
2611 : 175636 : newexpr->funcresulttype = expr->funcresulttype;
2612 : 175636 : newexpr->funcretset = expr->funcretset;
4101 tgl@sss.pgh.pa.us 2613 : 175636 : newexpr->funcvariadic = expr->funcvariadic;
4521 bruce@momjian.us 2614 : 175636 : newexpr->funcformat = expr->funcformat;
2615 : 175636 : newexpr->funccollid = expr->funccollid;
2616 : 175636 : newexpr->inputcollid = expr->inputcollid;
2617 : 175636 : newexpr->args = args;
2618 : 175636 : newexpr->location = expr->location;
2619 : 175636 : return (Node *) newexpr;
2620 : : }
tgl@sss.pgh.pa.us 2621 : 307495 : case T_OpExpr:
2622 : : {
bruce@momjian.us 2623 : 307495 : OpExpr *expr = (OpExpr *) node;
4405 tgl@sss.pgh.pa.us 2624 : 307495 : List *args = expr->args;
2625 : : Expr *simple;
2626 : : OpExpr *newexpr;
2627 : :
2628 : : /*
2629 : : * Need to get OID of underlying function. Okay to scribble
2630 : : * on input to this extent.
2631 : : */
4521 bruce@momjian.us 2632 : 307495 : set_opfuncid(expr);
2633 : :
2634 : : /*
2635 : : * Code for op/func reduction is pretty bulky, so split it out
2636 : : * as a separate function.
2637 : : */
4405 tgl@sss.pgh.pa.us 2638 : 307495 : simple = simplify_function(expr->opfuncid,
2639 : : expr->opresulttype, -1,
2640 : : expr->opcollid,
2641 : : expr->inputcollid,
2642 : : &args,
2643 : : false,
2644 : : true,
2645 : : true,
2646 : : context);
4521 bruce@momjian.us 2647 [ + + ]: 306946 : if (simple) /* successfully simplified it */
2648 : 9002 : return (Node *) simple;
2649 : :
2650 : : /*
2651 : : * If the operator is boolean equality or inequality, we know
2652 : : * how to simplify cases involving one constant and one
2653 : : * non-constant argument.
2654 : : */
2655 [ + + ]: 297944 : if (expr->opno == BooleanEqualOperator ||
2656 [ + + ]: 297747 : expr->opno == BooleanNotEqualOperator)
2657 : : {
tgl@sss.pgh.pa.us 2658 : 278 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2659 : : args);
bruce@momjian.us 2660 [ + + ]: 278 : if (simple) /* successfully simplified it */
2661 : 189 : return (Node *) simple;
2662 : : }
2663 : :
2664 : : /*
2665 : : * The expression cannot be simplified any further, so build
2666 : : * and return a replacement OpExpr node using the
2667 : : * possibly-simplified arguments.
2668 : : */
2669 : 297755 : newexpr = makeNode(OpExpr);
2670 : 297755 : newexpr->opno = expr->opno;
2671 : 297755 : newexpr->opfuncid = expr->opfuncid;
2672 : 297755 : newexpr->opresulttype = expr->opresulttype;
2673 : 297755 : newexpr->opretset = expr->opretset;
2674 : 297755 : newexpr->opcollid = expr->opcollid;
2675 : 297755 : newexpr->inputcollid = expr->inputcollid;
2676 : 297755 : newexpr->args = args;
2677 : 297755 : newexpr->location = expr->location;
2678 : 297755 : return (Node *) newexpr;
2679 : : }
tgl@sss.pgh.pa.us 2680 : 435 : case T_DistinctExpr:
2681 : : {
bruce@momjian.us 2682 : 435 : DistinctExpr *expr = (DistinctExpr *) node;
2683 : : List *args;
2684 : : ListCell *arg;
2685 : 435 : bool has_null_input = false;
2686 : 435 : bool all_null_input = true;
2687 : 435 : bool has_nonconst_input = false;
2688 : : Expr *simple;
2689 : : DistinctExpr *newexpr;
2690 : :
2691 : : /*
2692 : : * Reduce constants in the DistinctExpr's arguments. We know
2693 : : * args is either NIL or a List node, so we can call
2694 : : * expression_tree_mutator directly rather than recursing to
2695 : : * self.
2696 : : */
2697 : 435 : args = (List *) expression_tree_mutator((Node *) expr->args,
2698 : : eval_const_expressions_mutator,
2699 : : (void *) context);
2700 : :
2701 : : /*
2702 : : * We must do our own check for NULLs because DistinctExpr has
2703 : : * different results for NULL input than the underlying
2704 : : * operator does.
2705 : : */
2706 [ + - + + : 1305 : foreach(arg, args)
+ + ]
2707 : : {
2708 [ + + ]: 870 : if (IsA(lfirst(arg), Const))
2709 : : {
2710 : 45 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2711 : 45 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2712 : : }
2713 : : else
2714 : 825 : has_nonconst_input = true;
2715 : : }
2716 : :
2717 : : /* all constants? then can optimize this out */
2718 [ + + ]: 435 : if (!has_nonconst_input)
2719 : : {
2720 : : /* all nulls? then not distinct */
2721 [ - + ]: 12 : if (all_null_input)
4521 bruce@momjian.us 2722 :UBC 0 : return makeBoolConst(false, false);
2723 : :
2724 : : /* one null? then distinct */
4521 bruce@momjian.us 2725 [ - + ]:CBC 12 : if (has_null_input)
4521 bruce@momjian.us 2726 :UBC 0 : return makeBoolConst(true, false);
2727 : :
2728 : : /* otherwise try to evaluate the '=' operator */
2729 : : /* (NOT okay to try to inline it, though!) */
2730 : :
2731 : : /*
2732 : : * Need to get OID of underlying function. Okay to
2733 : : * scribble on input to this extent.
2734 : : */
2489 tgl@sss.pgh.pa.us 2735 :CBC 12 : set_opfuncid((OpExpr *) expr); /* rely on struct
2736 : : * equivalence */
2737 : :
2738 : : /*
2739 : : * Code for op/func reduction is pretty bulky, so split it
2740 : : * out as a separate function.
2741 : : */
4405 2742 : 12 : simple = simplify_function(expr->opfuncid,
2743 : : expr->opresulttype, -1,
2744 : : expr->opcollid,
2745 : : expr->inputcollid,
2746 : : &args,
2747 : : false,
2748 : : false,
2749 : : false,
2750 : : context);
4521 bruce@momjian.us 2751 [ + - ]: 12 : if (simple) /* successfully simplified it */
2752 : : {
2753 : : /*
2754 : : * Since the underlying operator is "=", must negate
2755 : : * its result
2756 : : */
2609 peter_e@gmx.net 2757 : 12 : Const *csimple = castNode(Const, simple);
2758 : :
4521 bruce@momjian.us 2759 : 12 : csimple->constvalue =
2760 : 12 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
2761 : 12 : return (Node *) csimple;
2762 : : }
2763 : : }
2764 : :
2765 : : /*
2766 : : * The expression cannot be simplified any further, so build
2767 : : * and return a replacement DistinctExpr node using the
2768 : : * possibly-simplified arguments.
2769 : : */
2770 : 423 : newexpr = makeNode(DistinctExpr);
2771 : 423 : newexpr->opno = expr->opno;
2772 : 423 : newexpr->opfuncid = expr->opfuncid;
2773 : 423 : newexpr->opresulttype = expr->opresulttype;
2774 : 423 : newexpr->opretset = expr->opretset;
2775 : 423 : newexpr->opcollid = expr->opcollid;
2776 : 423 : newexpr->inputcollid = expr->inputcollid;
2777 : 423 : newexpr->args = args;
2778 : 423 : newexpr->location = expr->location;
2779 : 423 : return (Node *) newexpr;
2780 : : }
1108 peter@eisentraut.org 2781 : 94 : case T_NullIfExpr:
2782 : : {
2783 : : NullIfExpr *expr;
2784 : : ListCell *arg;
1068 tgl@sss.pgh.pa.us 2785 : 94 : bool has_nonconst_input = false;
2786 : :
2787 : : /* Copy the node and const-simplify its arguments */
1108 peter@eisentraut.org 2788 : 94 : expr = (NullIfExpr *) ece_generic_processing(node);
2789 : :
2790 : : /* If either argument is NULL they can't be equal */
2791 [ + - + + : 279 : foreach(arg, expr->args)
+ + ]
2792 : : {
2793 [ + + ]: 188 : if (!IsA(lfirst(arg), Const))
2794 : 78 : has_nonconst_input = true;
2795 [ + + ]: 110 : else if (((Const *) lfirst(arg))->constisnull)
2796 : 3 : return (Node *) linitial(expr->args);
2797 : : }
2798 : :
2799 : : /*
2800 : : * Need to get OID of underlying function before checking if
2801 : : * the function is OK to evaluate.
2802 : : */
2803 : 91 : set_opfuncid((OpExpr *) expr);
2804 : :
2805 [ + + + - ]: 110 : if (!has_nonconst_input &&
2806 : 19 : ece_function_is_safe(expr->opfuncid, context))
2807 : 19 : return ece_evaluate_expr(expr);
2808 : :
2809 : 72 : return (Node *) expr;
2810 : : }
2293 tgl@sss.pgh.pa.us 2811 : 15802 : case T_ScalarArrayOpExpr:
2812 : : {
2813 : : ScalarArrayOpExpr *saop;
2814 : :
2815 : : /* Copy the node and const-simplify its arguments */
2816 : 15802 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
2817 : :
2818 : : /* Make sure we know underlying function */
2819 : 15802 : set_sa_opfuncid(saop);
2820 : :
2821 : : /*
2822 : : * If all arguments are Consts, and it's a safe function, we
2823 : : * can fold to a constant
2824 : : */
2825 [ + + + - ]: 15898 : if (ece_all_arguments_const(saop) &&
2826 : 96 : ece_function_is_safe(saop->opfuncid, context))
2827 : 96 : return ece_evaluate_expr(saop);
2828 : 15706 : return (Node *) saop;
2829 : : }
4521 2830 : 72926 : case T_BoolExpr:
2831 : : {
bruce@momjian.us 2832 : 72926 : BoolExpr *expr = (BoolExpr *) node;
2833 : :
2834 [ + + + - ]: 72926 : switch (expr->boolop)
2835 : : {
2836 : 6188 : case OR_EXPR:
2837 : : {
2838 : : List *newargs;
2839 : 6188 : bool haveNull = false;
2840 : 6188 : bool forceTrue = false;
2841 : :
tgl@sss.pgh.pa.us 2842 : 6188 : newargs = simplify_or_arguments(expr->args,
2843 : : context,
2844 : : &haveNull,
2845 : : &forceTrue);
bruce@momjian.us 2846 [ + + ]: 6188 : if (forceTrue)
2847 : 72 : return makeBoolConst(true, false);
2848 [ + + ]: 6116 : if (haveNull)
tgl@sss.pgh.pa.us 2849 : 15 : newargs = lappend(newargs,
2850 : 15 : makeBoolConst(false, true));
2851 : : /* If all the inputs are FALSE, result is FALSE */
bruce@momjian.us 2852 [ + + ]: 6116 : if (newargs == NIL)
2853 : 3 : return makeBoolConst(false, false);
2854 : :
2855 : : /*
2856 : : * If only one nonconst-or-NULL input, it's the
2857 : : * result
2858 : : */
2859 [ + + ]: 6113 : if (list_length(newargs) == 1)
2860 : 48 : return (Node *) linitial(newargs);
2861 : : /* Else we still need an OR node */
2862 : 6065 : return (Node *) make_orclause(newargs);
2863 : : }
2864 : 60788 : case AND_EXPR:
2865 : : {
2866 : : List *newargs;
2867 : 60788 : bool haveNull = false;
2868 : 60788 : bool forceFalse = false;
2869 : :
tgl@sss.pgh.pa.us 2870 : 60788 : newargs = simplify_and_arguments(expr->args,
2871 : : context,
2872 : : &haveNull,
2873 : : &forceFalse);
bruce@momjian.us 2874 [ + + ]: 60788 : if (forceFalse)
2875 : 733 : return makeBoolConst(false, false);
2876 [ + + ]: 60055 : if (haveNull)
tgl@sss.pgh.pa.us 2877 : 3 : newargs = lappend(newargs,
2878 : 3 : makeBoolConst(false, true));
2879 : : /* If all the inputs are TRUE, result is TRUE */
bruce@momjian.us 2880 [ + + ]: 60055 : if (newargs == NIL)
2881 : 181 : return makeBoolConst(true, false);
2882 : :
2883 : : /*
2884 : : * If only one nonconst-or-NULL input, it's the
2885 : : * result
2886 : : */
2887 [ + + ]: 59874 : if (list_length(newargs) == 1)
2888 : 13 : return (Node *) linitial(newargs);
2889 : : /* Else we still need an AND node */
2890 : 59861 : return (Node *) make_andclause(newargs);
2891 : : }
2892 : 5950 : case NOT_EXPR:
2893 : : {
2894 : : Node *arg;
2895 : :
2896 [ - + ]: 5950 : Assert(list_length(expr->args) == 1);
2897 : 5950 : arg = eval_const_expressions_mutator(linitial(expr->args),
2898 : : context);
2899 : :
2900 : : /*
2901 : : * Use negate_clause() to see if we can simplify
2902 : : * away the NOT.
2903 : : */
2904 : 5950 : return negate_clause(arg);
2905 : : }
4521 bruce@momjian.us 2906 :UBC 0 : default:
2907 [ # # ]: 0 : elog(ERROR, "unrecognized boolop: %d",
2908 : : (int) expr->boolop);
2909 : : break;
2910 : : }
2911 : : break;
2912 : : }
2913 : :
382 alvherre@alvh.no-ip. 2914 :CBC 333 : case T_JsonValueExpr:
2915 : : {
2916 : 333 : JsonValueExpr *jve = (JsonValueExpr *) node;
2917 : : Node *formatted;
2918 : :
282 amitlan@postgresql.o 2919 : 333 : formatted = eval_const_expressions_mutator((Node *) jve->formatted_expr,
2920 : : context);
2921 [ + - + + ]: 333 : if (formatted && IsA(formatted, Const))
2922 : 243 : return formatted;
382 alvherre@alvh.no-ip. 2923 : 90 : break;
2924 : : }
2925 : :
4521 tgl@sss.pgh.pa.us 2926 : 252 : case T_SubPlan:
2927 : : case T_AlternativeSubPlan:
2928 : :
2929 : : /*
2930 : : * Return a SubPlan unchanged --- too late to do anything with it.
2931 : : *
2932 : : * XXX should we ereport() here instead? Probably this routine
2933 : : * should never be invoked after SubPlan creation.
2934 : : */
bruce@momjian.us 2935 : 252 : return node;
tgl@sss.pgh.pa.us 2936 : 66829 : case T_RelabelType:
2937 : : {
bruce@momjian.us 2938 : 66829 : RelabelType *relabel = (RelabelType *) node;
2939 : : Node *arg;
2940 : :
2941 : : /* Simplify the input ... */
2942 : 66829 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
2943 : : context);
2944 : : /* ... and attach a new RelabelType node, if needed */
1334 tgl@sss.pgh.pa.us 2945 : 66829 : return applyRelabelType(arg,
2946 : : relabel->resulttype,
2947 : : relabel->resulttypmod,
2948 : : relabel->resultcollid,
2949 : : relabel->relabelformat,
2950 : : relabel->location,
2951 : : true);
2952 : : }
4521 2953 : 11386 : case T_CoerceViaIO:
2954 : : {
bruce@momjian.us 2955 : 11386 : CoerceViaIO *expr = (CoerceViaIO *) node;
2956 : : List *args;
2957 : : Oid outfunc;
2958 : : bool outtypisvarlena;
2959 : : Oid infunc;
2960 : : Oid intypioparam;
2961 : : Expr *simple;
2962 : : CoerceViaIO *newexpr;
2963 : :
2964 : : /* Make a List so we can use simplify_function */
4405 tgl@sss.pgh.pa.us 2965 : 11386 : args = list_make1(expr->arg);
2966 : :
2967 : : /*
2968 : : * CoerceViaIO represents calling the source type's output
2969 : : * function then the result type's input function. So, try to
2970 : : * simplify it as though it were a stack of two such function
2971 : : * calls. First we need to know what the functions are.
2972 : : *
2973 : : * Note that the coercion functions are assumed not to care
2974 : : * about input collation, so we just pass InvalidOid for that.
2975 : : */
2976 : 11386 : getTypeOutputInfo(exprType((Node *) expr->arg),
2977 : : &outfunc, &outtypisvarlena);
4521 2978 : 11386 : getTypeInputInfo(expr->resulttype,
2979 : : &infunc, &intypioparam);
2980 : :
4405 2981 : 11386 : simple = simplify_function(outfunc,
2982 : : CSTRINGOID, -1,
2983 : : InvalidOid,
2984 : : InvalidOid,
2985 : : &args,
2986 : : false,
2987 : : true,
2988 : : true,
2989 : : context);
4521 bruce@momjian.us 2990 [ + + ]: 11386 : if (simple) /* successfully simplified output fn */
2991 : : {
2992 : : /*
2993 : : * Input functions may want 1 to 3 arguments. We always
2994 : : * supply all three, trusting that nothing downstream will
2995 : : * complain.
2996 : : */
2997 : 1009 : args = list_make3(simple,
2998 : : makeConst(OIDOID,
2999 : : -1,
3000 : : InvalidOid,
3001 : : sizeof(Oid),
3002 : : ObjectIdGetDatum(intypioparam),
3003 : : false,
3004 : : true),
3005 : : makeConst(INT4OID,
3006 : : -1,
3007 : : InvalidOid,
3008 : : sizeof(int32),
3009 : : Int32GetDatum(-1),
3010 : : false,
3011 : : true));
3012 : :
4405 tgl@sss.pgh.pa.us 3013 : 1009 : simple = simplify_function(infunc,
3014 : : expr->resulttype, -1,
3015 : : expr->resultcollid,
3016 : : InvalidOid,
3017 : : &args,
3018 : : false,
3019 : : false,
3020 : : true,
3021 : : context);
4521 bruce@momjian.us 3022 [ + + ]: 983 : if (simple) /* successfully simplified input fn */
3023 : 958 : return (Node *) simple;
3024 : : }
3025 : :
3026 : : /*
3027 : : * The expression cannot be simplified any further, so build
3028 : : * and return a replacement CoerceViaIO node using the
3029 : : * possibly-simplified argument.
3030 : : */
3031 : 10402 : newexpr = makeNode(CoerceViaIO);
4405 tgl@sss.pgh.pa.us 3032 : 10402 : newexpr->arg = (Expr *) linitial(args);
4521 bruce@momjian.us 3033 : 10402 : newexpr->resulttype = expr->resulttype;
3034 : 10402 : newexpr->resultcollid = expr->resultcollid;
3035 : 10402 : newexpr->coerceformat = expr->coerceformat;
3036 : 10402 : newexpr->location = expr->location;
3037 : 10402 : return (Node *) newexpr;
3038 : : }
tgl@sss.pgh.pa.us 3039 : 4361 : case T_ArrayCoerceExpr:
3040 : : {
1993 3041 : 4361 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3042 : : Node *save_case_val;
3043 : :
3044 : : /*
3045 : : * Copy the node and const-simplify its arguments. We can't
3046 : : * use ece_generic_processing() here because we need to mess
3047 : : * with case_val only while processing the elemexpr.
3048 : : */
3049 : 4361 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3050 : 4361 : ac->arg = (Expr *)
3051 : 4361 : eval_const_expressions_mutator((Node *) ac->arg,
3052 : : context);
3053 : :
3054 : : /*
3055 : : * Set up for the CaseTestExpr node contained in the elemexpr.
3056 : : * We must prevent it from absorbing any outer CASE value.
3057 : : */
3058 : 4361 : save_case_val = context->case_val;
3059 : 4361 : context->case_val = NULL;
3060 : :
3061 : 4361 : ac->elemexpr = (Expr *)
3062 : 4361 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3063 : : context);
3064 : :
3065 : 4361 : context->case_val = save_case_val;
3066 : :
3067 : : /*
3068 : : * If constant argument and the per-element expression is
3069 : : * immutable, we can simplify the whole thing to a constant.
3070 : : * Exception: although contain_mutable_functions considers
3071 : : * CoerceToDomain immutable for historical reasons, let's not
3072 : : * do so here; this ensures coercion to an array-over-domain
3073 : : * does not apply the domain's constraints until runtime.
3074 : : */
2293 3075 [ + - + + ]: 4361 : if (ac->arg && IsA(ac->arg, Const) &&
3076 [ + - + + ]: 492 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3077 [ + - ]: 480 : !contain_mutable_functions((Node *) ac->elemexpr))
3078 : 480 : return ece_evaluate_expr(ac);
3079 : :
3080 : 3881 : return (Node *) ac;
3081 : : }
4521 bruce@momjian.us 3082 : 3821 : case T_CollateExpr:
3083 : : {
3084 : : /*
3085 : : * We replace CollateExpr with RelabelType, so as to improve
3086 : : * uniformity of expression representation and thus simplify
3087 : : * comparison of expressions. Hence this looks very nearly
3088 : : * the same as the RelabelType case, and we can apply the same
3089 : : * optimizations to avoid unnecessary RelabelTypes.
3090 : : */
3091 : 3821 : CollateExpr *collate = (CollateExpr *) node;
3092 : : Node *arg;
3093 : :
3094 : : /* Simplify the input ... */
3095 : 3821 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3096 : : context);
3097 : : /* ... and attach a new RelabelType node, if needed */
1334 tgl@sss.pgh.pa.us 3098 : 3821 : return applyRelabelType(arg,
3099 : : exprType(arg),
3100 : : exprTypmod(arg),
3101 : : collate->collOid,
3102 : : COERCE_IMPLICIT_CAST,
3103 : : collate->location,
3104 : : true);
3105 : : }
4521 bruce@momjian.us 3106 : 22588 : case T_CaseExpr:
3107 : : {
3108 : : /*----------
3109 : : * CASE expressions can be simplified if there are constant
3110 : : * condition clauses:
3111 : : * FALSE (or NULL): drop the alternative
3112 : : * TRUE: drop all remaining alternatives
3113 : : * If the first non-FALSE alternative is a constant TRUE,
3114 : : * we can simplify the entire CASE to that alternative's
3115 : : * expression. If there are no non-FALSE alternatives,
3116 : : * we simplify the entire CASE to the default result (ELSE).
3117 : : *
3118 : : * If we have a simple-form CASE with constant test
3119 : : * expression, we substitute the constant value for contained
3120 : : * CaseTestExpr placeholder nodes, so that we have the
3121 : : * opportunity to reduce constant test conditions. For
3122 : : * example this allows
3123 : : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3124 : : * to reduce to 1 rather than drawing a divide-by-0 error.
3125 : : * Note that when the test expression is constant, we don't
3126 : : * have to include it in the resulting CASE; for example
3127 : : * CASE 0 WHEN x THEN y ELSE z END
3128 : : * is transformed by the parser to
3129 : : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3130 : : * which we can simplify to
3131 : : * CASE WHEN 0 = x THEN y ELSE z END
3132 : : * It is not necessary for the executor to evaluate the "arg"
3133 : : * expression when executing the CASE, since any contained
3134 : : * CaseTestExprs that might have referred to it will have been
3135 : : * replaced by the constant.
3136 : : *----------
3137 : : */
3138 : 22588 : CaseExpr *caseexpr = (CaseExpr *) node;
3139 : : CaseExpr *newcase;
3140 : : Node *save_case_val;
3141 : : Node *newarg;
3142 : : List *newargs;
3143 : : bool const_true_cond;
3144 : 22588 : Node *defresult = NULL;
3145 : : ListCell *arg;
3146 : :
3147 : : /* Simplify the test expression, if any */
3148 : 22588 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3149 : : context);
3150 : :
3151 : : /* Set up for contained CaseTestExpr nodes */
3152 : 22588 : save_case_val = context->case_val;
3153 [ + + + + ]: 22588 : if (newarg && IsA(newarg, Const))
3154 : : {
3155 : 9 : context->case_val = newarg;
2489 tgl@sss.pgh.pa.us 3156 : 9 : newarg = NULL; /* not needed anymore, see above */
3157 : : }
3158 : : else
4521 bruce@momjian.us 3159 : 22579 : context->case_val = NULL;
3160 : :
3161 : : /* Simplify the WHEN clauses */
3162 : 22588 : newargs = NIL;
3163 : 22588 : const_true_cond = false;
3164 [ + - + + : 60053 : foreach(arg, caseexpr->args)
+ + ]
3165 : : {
2561 tgl@sss.pgh.pa.us 3166 : 37628 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3167 : : Node *casecond;
3168 : : Node *caseresult;
3169 : :
3170 : : /* Simplify this alternative's test condition */
4521 3171 : 37628 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3172 : : context);
3173 : :
3174 : : /*
3175 : : * If the test condition is constant FALSE (or NULL), then
3176 : : * drop this WHEN clause completely, without processing
3177 : : * the result.
3178 : : */
bruce@momjian.us 3179 [ + - + + ]: 37628 : if (casecond && IsA(casecond, Const))
3180 : : {
3181 : 493 : Const *const_input = (Const *) casecond;
3182 : :
3183 [ + - ]: 493 : if (const_input->constisnull ||
3184 [ + + ]: 493 : !DatumGetBool(const_input->constvalue))
tgl@sss.pgh.pa.us 3185 : 333 : continue; /* drop alternative with FALSE cond */
3186 : : /* Else it's constant TRUE */
bruce@momjian.us 3187 : 160 : const_true_cond = true;
3188 : : }
3189 : :
3190 : : /* Simplify this alternative's result value */
tgl@sss.pgh.pa.us 3191 : 37295 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3192 : : context);
3193 : :
3194 : : /* If non-constant test condition, emit a new WHEN node */
bruce@momjian.us 3195 [ + + ]: 37292 : if (!const_true_cond)
3196 : 37132 : {
3197 : 37132 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3198 : :
3199 : 37132 : newcasewhen->expr = (Expr *) casecond;
3200 : 37132 : newcasewhen->result = (Expr *) caseresult;
3201 : 37132 : newcasewhen->location = oldcasewhen->location;
3202 : 37132 : newargs = lappend(newargs, newcasewhen);
3203 : 37132 : continue;
3204 : : }
3205 : :
3206 : : /*
3207 : : * Found a TRUE condition, so none of the remaining
3208 : : * alternatives can be reached. We treat the result as
3209 : : * the default result.
3210 : : */
3211 : 160 : defresult = caseresult;
3212 : 160 : break;
3213 : : }
3214 : :
3215 : : /* Simplify the default result, unless we replaced it above */
3216 [ + + ]: 22585 : if (!const_true_cond)
tgl@sss.pgh.pa.us 3217 : 22425 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3218 : : context);
3219 : :
bruce@momjian.us 3220 : 22585 : context->case_val = save_case_val;
3221 : :
3222 : : /*
3223 : : * If no non-FALSE alternatives, CASE reduces to the default
3224 : : * result
3225 : : */
3226 [ + + ]: 22585 : if (newargs == NIL)
3227 : 268 : return defresult;
3228 : : /* Otherwise we need a new CASE node */
3229 : 22317 : newcase = makeNode(CaseExpr);
3230 : 22317 : newcase->casetype = caseexpr->casetype;
3231 : 22317 : newcase->casecollid = caseexpr->casecollid;
3232 : 22317 : newcase->arg = (Expr *) newarg;
3233 : 22317 : newcase->args = newargs;
3234 : 22317 : newcase->defresult = (Expr *) defresult;
3235 : 22317 : newcase->location = caseexpr->location;
3236 : 22317 : return (Node *) newcase;
3237 : : }
tgl@sss.pgh.pa.us 3238 : 14184 : case T_CaseTestExpr:
3239 : : {
3240 : : /*
3241 : : * If we know a constant test value for the current CASE
3242 : : * construct, substitute it for the placeholder. Else just
3243 : : * return the placeholder as-is.
3244 : : */
bruce@momjian.us 3245 [ + + ]: 14184 : if (context->case_val)
3246 : 12 : return copyObject(context->case_val);
3247 : : else
3248 : 14172 : return copyObject(node);
3249 : : }
1899 alvherre@alvh.no-ip. 3250 : 24828 : case T_SubscriptingRef:
3251 : : case T_ArrayExpr:
3252 : : case T_RowExpr:
3253 : : case T_MinMaxExpr:
3254 : : {
3255 : : /*
3256 : : * Generic handling for node types whose own processing is
3257 : : * known to be immutable, and for which we need no smarts
3258 : : * beyond "simplify if all inputs are constants".
3259 : : *
3260 : : * Treating SubscriptingRef this way assumes that subscripting
3261 : : * fetch and assignment are both immutable. This constrains
3262 : : * type-specific subscripting implementations; maybe we should
3263 : : * relax it someday.
3264 : : *
3265 : : * Treating MinMaxExpr this way amounts to assuming that the
3266 : : * btree comparison function it calls is immutable; see the
3267 : : * reasoning in contain_mutable_functions_walker.
3268 : : */
3269 : :
3270 : : /* Copy the node and const-simplify its arguments */
2293 tgl@sss.pgh.pa.us 3271 : 24828 : node = ece_generic_processing(node);
3272 : : /* If all arguments are Consts, we can fold to a constant */
3273 [ + + ]: 24828 : if (ece_all_arguments_const(node))
3274 : 13123 : return ece_evaluate_expr(node);
3275 : 11705 : return node;
3276 : : }
4521 3277 : 1275 : case T_CoalesceExpr:
3278 : : {
bruce@momjian.us 3279 : 1275 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3280 : : CoalesceExpr *newcoalesce;
3281 : : List *newargs;
3282 : : ListCell *arg;
3283 : :
3284 : 1275 : newargs = NIL;
3285 [ + - + + : 3051 : foreach(arg, coalesceexpr->args)
+ + ]
3286 : : {
3287 : : Node *e;
3288 : :
3289 : 2520 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3290 : : context);
3291 : :
3292 : : /*
3293 : : * We can remove null constants from the list. For a
3294 : : * non-null constant, if it has not been preceded by any
3295 : : * other non-null-constant expressions then it is the
3296 : : * result. Otherwise, it's the next argument, but we can
3297 : : * drop following arguments since they will never be
3298 : : * reached.
3299 : : */
3300 [ + + ]: 2520 : if (IsA(e, Const))
3301 : : {
3302 [ + + ]: 763 : if (((Const *) e)->constisnull)
3303 : 19 : continue; /* drop null constant */
3304 [ + + ]: 744 : if (newargs == NIL)
3305 : 34 : return e; /* first expr */
3306 : 710 : newargs = lappend(newargs, e);
3307 : 710 : break;
3308 : : }
3309 : 1757 : newargs = lappend(newargs, e);
3310 : : }
3311 : :
3312 : : /*
3313 : : * If all the arguments were constant null, the result is just
3314 : : * null
3315 : : */
7257 tgl@sss.pgh.pa.us 3316 [ - + ]: 1241 : if (newargs == NIL)
4521 bruce@momjian.us 3317 :UBC 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3318 : : -1,
3319 : : coalesceexpr->coalescecollid);
3320 : :
4521 bruce@momjian.us 3321 :CBC 1241 : newcoalesce = makeNode(CoalesceExpr);
3322 : 1241 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3323 : 1241 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3324 : 1241 : newcoalesce->args = newargs;
3325 : 1241 : newcoalesce->location = coalesceexpr->location;
3326 : 1241 : return (Node *) newcoalesce;
3327 : : }
333 michael@paquier.xyz 3328 : 2384 : case T_SQLValueFunction:
3329 : : {
3330 : : /*
3331 : : * All variants of SQLValueFunction are stable, so if we are
3332 : : * estimating the expression's value, we should evaluate the
3333 : : * current function value. Otherwise just copy.
3334 : : */
3335 : 2384 : SQLValueFunction *svf = (SQLValueFunction *) node;
3336 : :
3337 [ + + ]: 2384 : if (context->estimate)
3338 : 405 : return (Node *) evaluate_expr((Expr *) svf,
3339 : : svf->type,
3340 : : svf->typmod,
3341 : : InvalidOid);
3342 : : else
3343 : 1979 : return copyObject((Node *) svf);
3344 : : }
4521 tgl@sss.pgh.pa.us 3345 : 2181 : case T_FieldSelect:
3346 : : {
3347 : : /*
3348 : : * We can optimize field selection from a whole-row Var into a
3349 : : * simple Var. (This case won't be generated directly by the
3350 : : * parser, because ParseComplexProjection short-circuits it.
3351 : : * But it can arise while simplifying functions.) Also, we
3352 : : * can optimize field selection from a RowExpr construct, or
3353 : : * of course from a constant.
3354 : : *
3355 : : * However, replacing a whole-row Var in this way has a
3356 : : * pitfall: if we've already built the rel targetlist for the
3357 : : * source relation, then the whole-row Var is scheduled to be
3358 : : * produced by the relation scan, but the simple Var probably
3359 : : * isn't, which will lead to a failure in setrefs.c. This is
3360 : : * not a problem when handling simple single-level queries, in
3361 : : * which expression simplification always happens first. It
3362 : : * is a risk for lateral references from subqueries, though.
3363 : : * To avoid such failures, don't optimize uplevel references.
3364 : : *
3365 : : * We must also check that the declared type of the field is
3366 : : * still the same as when the FieldSelect was created --- this
3367 : : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3368 : : * If it isn't, we skip the optimization; the case will
3369 : : * probably fail at runtime, but that's not our problem here.
3370 : : */
bruce@momjian.us 3371 : 2181 : FieldSelect *fselect = (FieldSelect *) node;
3372 : : FieldSelect *newfselect;
3373 : : Node *arg;
3374 : :
3375 : 2181 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3376 : : context);
3377 [ + - + + ]: 2181 : if (arg && IsA(arg, Var) &&
3464 tgl@sss.pgh.pa.us 3378 [ + + ]: 264 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3379 [ + + ]: 45 : ((Var *) arg)->varlevelsup == 0)
3380 : : {
4521 bruce@momjian.us 3381 [ + - ]: 39 : if (rowtype_field_matches(((Var *) arg)->vartype,
3382 : 39 : fselect->fieldnum,
3383 : : fselect->resulttype,
3384 : : fselect->resulttypmod,
3385 : : fselect->resultcollid))
3386 : : {
3387 : : Var *newvar;
3388 : :
157 tgl@sss.pgh.pa.us 3389 : 39 : newvar = makeVar(((Var *) arg)->varno,
3390 : 39 : fselect->fieldnum,
3391 : : fselect->resulttype,
3392 : : fselect->resulttypmod,
3393 : : fselect->resultcollid,
3394 : : ((Var *) arg)->varlevelsup);
3395 : : /* New Var is nullable by same rels as the old one */
3396 : 39 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3397 : 39 : return (Node *) newvar;
3398 : : }
3399 : : }
4521 bruce@momjian.us 3400 [ + - + + ]: 2142 : if (arg && IsA(arg, RowExpr))
3401 : : {
3402 : 12 : RowExpr *rowexpr = (RowExpr *) arg;
3403 : :
3404 [ + - + - ]: 24 : if (fselect->fieldnum > 0 &&
3405 : 12 : fselect->fieldnum <= list_length(rowexpr->args))
3406 : : {
3407 : 12 : Node *fld = (Node *) list_nth(rowexpr->args,
2489 tgl@sss.pgh.pa.us 3408 : 12 : fselect->fieldnum - 1);
3409 : :
4521 bruce@momjian.us 3410 [ + - ]: 12 : if (rowtype_field_matches(rowexpr->row_typeid,
3411 : 12 : fselect->fieldnum,
3412 : : fselect->resulttype,
3413 : : fselect->resulttypmod,
3414 [ + - ]: 12 : fselect->resultcollid) &&
3415 [ + - ]: 24 : fselect->resulttype == exprType(fld) &&
3416 [ + - ]: 24 : fselect->resulttypmod == exprTypmod(fld) &&
3417 : 12 : fselect->resultcollid == exprCollation(fld))
3418 : 12 : return fld;
3419 : : }
3420 : : }
3421 : 2130 : newfselect = makeNode(FieldSelect);
3422 : 2130 : newfselect->arg = (Expr *) arg;
3423 : 2130 : newfselect->fieldnum = fselect->fieldnum;
3424 : 2130 : newfselect->resulttype = fselect->resulttype;
3425 : 2130 : newfselect->resulttypmod = fselect->resulttypmod;
3426 : 2130 : newfselect->resultcollid = fselect->resultcollid;
2293 tgl@sss.pgh.pa.us 3427 [ + - + + ]: 2130 : if (arg && IsA(arg, Const))
3428 : : {
3429 : 212 : Const *con = (Const *) arg;
3430 : :
3431 [ + - ]: 212 : if (rowtype_field_matches(con->consttype,
3432 : 212 : newfselect->fieldnum,
3433 : : newfselect->resulttype,
3434 : : newfselect->resulttypmod,
3435 : : newfselect->resultcollid))
3436 : 212 : return ece_evaluate_expr(newfselect);
3437 : : }
4521 bruce@momjian.us 3438 : 1918 : return (Node *) newfselect;
3439 : : }
tgl@sss.pgh.pa.us 3440 : 16790 : case T_NullTest:
3441 : : {
bruce@momjian.us 3442 : 16790 : NullTest *ntest = (NullTest *) node;
3443 : : NullTest *newntest;
3444 : : Node *arg;
3445 : :
3446 : 16790 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3447 : : context);
2819 tgl@sss.pgh.pa.us 3448 [ + + + - : 16789 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
+ + ]
3449 : : {
3450 : : /*
3451 : : * We break ROW(...) IS [NOT] NULL into separate tests on
3452 : : * its component fields. This form is usually more
3453 : : * efficient to evaluate, as well as being more amenable
3454 : : * to optimization.
3455 : : */
4521 bruce@momjian.us 3456 : 15 : RowExpr *rarg = (RowExpr *) arg;
3457 : 15 : List *newargs = NIL;
3458 : : ListCell *l;
3459 : :
3460 [ + - + + : 60 : foreach(l, rarg->args)
+ + ]
3461 : : {
3462 : 45 : Node *relem = (Node *) lfirst(l);
3463 : :
3464 : : /*
3465 : : * A constant field refutes the whole NullTest if it's
3466 : : * of the wrong nullness; else we can discard it.
3467 : : */
3468 [ + - - + ]: 45 : if (relem && IsA(relem, Const))
4521 bruce@momjian.us 3469 :UBC 0 : {
3470 : 0 : Const *carg = (Const *) relem;
3471 : :
3472 [ # # # # ]: 0 : if (carg->constisnull ?
3473 : 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3474 : 0 : (ntest->nulltesttype == IS_NULL))
3475 : 0 : return makeBoolConst(false, false);
3476 : 0 : continue;
3477 : : }
3478 : :
3479 : : /*
3480 : : * Else, make a scalar (argisrow == false) NullTest
3481 : : * for this field. Scalar semantics are required
3482 : : * because IS [NOT] NULL doesn't recurse; see comments
3483 : : * in ExecEvalRowNullInt().
3484 : : */
4521 bruce@momjian.us 3485 :CBC 45 : newntest = makeNode(NullTest);
3486 : 45 : newntest->arg = (Expr *) relem;
3487 : 45 : newntest->nulltesttype = ntest->nulltesttype;
2819 tgl@sss.pgh.pa.us 3488 : 45 : newntest->argisrow = false;
3339 3489 : 45 : newntest->location = ntest->location;
4521 bruce@momjian.us 3490 : 45 : newargs = lappend(newargs, newntest);
3491 : : }
3492 : : /* If all the inputs were constants, result is TRUE */
3493 [ - + ]: 15 : if (newargs == NIL)
4521 bruce@momjian.us 3494 :UBC 0 : return makeBoolConst(true, false);
3495 : : /* If only one nonconst input, it's the result */
4521 bruce@momjian.us 3496 [ - + ]:CBC 15 : if (list_length(newargs) == 1)
4521 bruce@momjian.us 3497 :UBC 0 : return (Node *) linitial(newargs);
3498 : : /* Else we need an AND node */
4521 bruce@momjian.us 3499 :CBC 15 : return (Node *) make_andclause(newargs);
3500 : : }
3501 [ + + + - : 16774 : if (!ntest->argisrow && arg && IsA(arg, Const))
+ + ]
3502 : : {
3503 : 184 : Const *carg = (Const *) arg;
3504 : : bool result;
3505 : :
3506 [ + + - ]: 184 : switch (ntest->nulltesttype)
3507 : : {
3508 : 155 : case IS_NULL:
3509 : 155 : result = carg->constisnull;
3510 : 155 : break;
3511 : 29 : case IS_NOT_NULL:
3512 : 29 : result = !carg->constisnull;
3513 : 29 : break;
4521 bruce@momjian.us 3514 :UBC 0 : default:
3515 [ # # ]: 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3516 : : (int) ntest->nulltesttype);
3517 : : result = false; /* keep compiler quiet */
3518 : : break;
3519 : : }
3520 : :
4521 bruce@momjian.us 3521 :CBC 184 : return makeBoolConst(result, false);
3522 : : }
3523 : :
6408 tgl@sss.pgh.pa.us 3524 : 16590 : newntest = makeNode(NullTest);
4521 bruce@momjian.us 3525 : 16590 : newntest->arg = (Expr *) arg;
6408 tgl@sss.pgh.pa.us 3526 : 16590 : newntest->nulltesttype = ntest->nulltesttype;
4521 bruce@momjian.us 3527 : 16590 : newntest->argisrow = ntest->argisrow;
3339 tgl@sss.pgh.pa.us 3528 : 16590 : newntest->location = ntest->location;
4521 bruce@momjian.us 3529 : 16590 : return (Node *) newntest;
3530 : : }
tgl@sss.pgh.pa.us 3531 : 912 : case T_BooleanTest:
3532 : : {
3533 : : /*
3534 : : * This case could be folded into the generic handling used
3535 : : * for ArrayExpr etc. But because the simplification logic is
3536 : : * so trivial, applying evaluate_expr() to perform it would be
3537 : : * a heavy overhead. BooleanTest is probably common enough to
3538 : : * justify keeping this bespoke implementation.
3539 : : */
bruce@momjian.us 3540 : 912 : BooleanTest *btest = (BooleanTest *) node;
3541 : : BooleanTest *newbtest;
3542 : : Node *arg;
3543 : :
3544 : 912 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3545 : : context);
3546 [ + - + + ]: 912 : if (arg && IsA(arg, Const))
3547 : : {
3548 : 111 : Const *carg = (Const *) arg;
3549 : : bool result;
3550 : :
3551 [ - + - - : 111 : switch (btest->booltesttype)
- - - ]
3552 : : {
4521 bruce@momjian.us 3553 :UBC 0 : case IS_TRUE:
3554 [ # # # # ]: 0 : result = (!carg->constisnull &&
3555 : 0 : DatumGetBool(carg->constvalue));
3556 : 0 : break;
4521 bruce@momjian.us 3557 :CBC 111 : case IS_NOT_TRUE:
3558 [ + - ]: 222 : result = (carg->constisnull ||
3559 [ + + ]: 111 : !DatumGetBool(carg->constvalue));
3560 : 111 : break;
4521 bruce@momjian.us 3561 :UBC 0 : case IS_FALSE:
3562 [ # # ]: 0 : result = (!carg->constisnull &&
3563 [ # # ]: 0 : !DatumGetBool(carg->constvalue));
3564 : 0 : break;
3565 : 0 : case IS_NOT_FALSE:
3566 [ # # # # ]: 0 : result = (carg->constisnull ||
3567 : 0 : DatumGetBool(carg->constvalue));
3568 : 0 : break;
3569 : 0 : case IS_UNKNOWN:
3570 : 0 : result = carg->constisnull;
3571 : 0 : break;
3572 : 0 : case IS_NOT_UNKNOWN:
3573 : 0 : result = !carg->constisnull;
3574 : 0 : break;
3575 : 0 : default:
3576 [ # # ]: 0 : elog(ERROR, "unrecognized booltesttype: %d",
3577 : : (int) btest->booltesttype);
3578 : : result = false; /* keep compiler quiet */
3579 : : break;
3580 : : }
3581 : :
4521 bruce@momjian.us 3582 :CBC 111 : return makeBoolConst(result, false);
3583 : : }
3584 : :
3585 : 801 : newbtest = makeNode(BooleanTest);
3586 : 801 : newbtest->arg = (Expr *) arg;
3587 : 801 : newbtest->booltesttype = btest->booltesttype;
3339 tgl@sss.pgh.pa.us 3588 : 801 : newbtest->location = btest->location;
4521 bruce@momjian.us 3589 : 801 : return (Node *) newbtest;
3590 : : }
1949 tgl@sss.pgh.pa.us 3591 : 11441 : case T_CoerceToDomain:
3592 : : {
3593 : : /*
3594 : : * If the domain currently has no constraints, we replace the
3595 : : * CoerceToDomain node with a simple RelabelType, which is
3596 : : * both far faster to execute and more amenable to later
3597 : : * optimization. We must then mark the plan as needing to be
3598 : : * rebuilt if the domain's constraints change.
3599 : : *
3600 : : * Also, in estimation mode, always replace CoerceToDomain
3601 : : * nodes, effectively assuming that the coercion will succeed.
3602 : : */
3603 : 11441 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
3604 : : CoerceToDomain *newcdomain;
3605 : : Node *arg;
3606 : :
3607 : 11441 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
3608 : : context);
3609 [ + + ]: 11429 : if (context->estimate ||
3610 [ + + ]: 11417 : !DomainHasConstraints(cdomain->resulttype))
3611 : : {
3612 : : /* Record dependency, if this isn't estimation mode */
3613 [ + + + - ]: 7480 : if (context->root && !context->estimate)
3614 : 7447 : record_plan_type_dependency(context->root,
3615 : : cdomain->resulttype);
3616 : :
3617 : : /* Generate RelabelType to substitute for CoerceToDomain */
1334 3618 : 7480 : return applyRelabelType(arg,
3619 : : cdomain->resulttype,
3620 : : cdomain->resulttypmod,
3621 : : cdomain->resultcollid,
3622 : : cdomain->coercionformat,
3623 : : cdomain->location,
3624 : : true);
3625 : : }
3626 : :
1949 3627 : 3949 : newcdomain = makeNode(CoerceToDomain);
3628 : 3949 : newcdomain->arg = (Expr *) arg;
3629 : 3949 : newcdomain->resulttype = cdomain->resulttype;
3630 : 3949 : newcdomain->resulttypmod = cdomain->resulttypmod;
3631 : 3949 : newcdomain->resultcollid = cdomain->resultcollid;
3632 : 3949 : newcdomain->coercionformat = cdomain->coercionformat;
3633 : 3949 : newcdomain->location = cdomain->location;
3634 : 3949 : return (Node *) newcdomain;
3635 : : }
4521 3636 : 1278 : case T_PlaceHolderVar:
3637 : :
3638 : : /*
3639 : : * In estimation mode, just strip the PlaceHolderVar node
3640 : : * altogether; this amounts to estimating that the contained value
3641 : : * won't be forced to null by an outer join. In regular mode we
3642 : : * just use the default behavior (ie, simplify the expression but
3643 : : * leave the PlaceHolderVar node intact).
3644 : : */
3645 [ + + ]: 1278 : if (context->estimate)
3646 : : {
3647 : 372 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
3648 : :
3649 : 372 : return eval_const_expressions_mutator((Node *) phv->phexpr,
3650 : : context);
3651 : : }
3652 : 906 : break;
1986 rhodiumtoad@postgres 3653 : 39 : case T_ConvertRowtypeExpr:
3654 : : {
3655 : 39 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
3656 : : Node *arg;
3657 : : ConvertRowtypeExpr *newcre;
3658 : :
3659 : 39 : arg = eval_const_expressions_mutator((Node *) cre->arg,
3660 : : context);
3661 : :
3662 : 39 : newcre = makeNode(ConvertRowtypeExpr);
3663 : 39 : newcre->resulttype = cre->resulttype;
3664 : 39 : newcre->convertformat = cre->convertformat;
3665 : 39 : newcre->location = cre->location;
3666 : :
3667 : : /*
3668 : : * In case of a nested ConvertRowtypeExpr, we can convert the
3669 : : * leaf row directly to the topmost row format without any
3670 : : * intermediate conversions. (This works because
3671 : : * ConvertRowtypeExpr is used only for child->parent
3672 : : * conversion in inheritance trees, which works by exact match
3673 : : * of column name, and a column absent in an intermediate
3674 : : * result can't be present in the final result.)
3675 : : *
3676 : : * No need to check more than one level deep, because the
3677 : : * above recursion will have flattened anything else.
3678 : : */
3679 [ + - + + ]: 39 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
3680 : : {
3681 : 6 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
3682 : :
3683 : 6 : arg = (Node *) argcre->arg;
3684 : :
3685 : : /*
3686 : : * Make sure an outer implicit conversion can't hide an
3687 : : * inner explicit one.
3688 : : */
3689 [ - + ]: 6 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
1986 rhodiumtoad@postgres 3690 :UBC 0 : newcre->convertformat = argcre->convertformat;
3691 : : }
3692 : :
1986 rhodiumtoad@postgres 3693 :CBC 39 : newcre->arg = (Expr *) arg;
3694 : :
3695 [ + - + + ]: 39 : if (arg != NULL && IsA(arg, Const))
3696 : 9 : return ece_evaluate_expr((Node *) newcre);
3697 : 30 : return (Node *) newcre;
3698 : : }
4521 tgl@sss.pgh.pa.us 3699 : 2786893 : default:
3700 : 2786893 : break;
3701 : : }
3702 : :
3703 : : /*
3704 : : * For any node type not handled above, copy the node unchanged but
3705 : : * const-simplify its subexpressions. This is the correct thing for node
3706 : : * types whose behavior might change between planning and execution, such
3707 : : * as CurrentOfExpr. It's also a safe default for new node types not
3708 : : * known to this routine.
3709 : : */
2293 3710 : 2787889 : return ece_generic_processing(node);
3711 : : }
3712 : :
3713 : : /*
3714 : : * Subroutine for eval_const_expressions: check for non-Const nodes.
3715 : : *
3716 : : * We can abort recursion immediately on finding a non-Const node. This is
3717 : : * critical for performance, else eval_const_expressions_mutator would take
3718 : : * O(N^2) time on non-simplifiable trees. However, we do need to descend
3719 : : * into List nodes since expression_tree_walker sometimes invokes the walker
3720 : : * function directly on List subtrees.
3721 : : */
3722 : : static bool
3723 : 88428 : contain_non_const_walker(Node *node, void *context)
3724 : : {
3725 [ + + ]: 88428 : if (node == NULL)
3726 : 299 : return false;
3727 [ + + ]: 88129 : if (IsA(node, Const))
3728 : 45033 : return false;
3729 [ + + ]: 43096 : if (IsA(node, List))
3730 : 15685 : return expression_tree_walker(node, contain_non_const_walker, context);
3731 : : /* Otherwise, abort the tree traversal and return true */
3732 : 27411 : return true;
3733 : : }
3734 : :
3735 : : /*
3736 : : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
3737 : : */
3738 : : static bool
3739 : 115 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
3740 : : {
3741 : 115 : char provolatile = func_volatile(funcid);
3742 : :
3743 : : /*
3744 : : * Ordinarily we are only allowed to simplify immutable functions. But for
3745 : : * purposes of estimation, we consider it okay to simplify functions that
3746 : : * are merely stable; the risk that the result might change from planning
3747 : : * time to execution time is worth taking in preference to not being able
3748 : : * to estimate the value at all.
3749 : : */
3750 [ + - ]: 115 : if (provolatile == PROVOLATILE_IMMUTABLE)
3751 : 115 : return true;
2293 tgl@sss.pgh.pa.us 3752 [ # # # # ]:UBC 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
3753 : 0 : return true;
3754 : 0 : return false;
3755 : : }
3756 : :
3757 : : /*
3758 : : * Subroutine for eval_const_expressions: process arguments of an OR clause
3759 : : *
3760 : : * This includes flattening of nested ORs as well as recursion to
3761 : : * eval_const_expressions to simplify the OR arguments.
3762 : : *
3763 : : * After simplification, OR arguments are handled as follows:
3764 : : * non constant: keep
3765 : : * FALSE: drop (does not affect result)
3766 : : * TRUE: force result to TRUE
3767 : : * NULL: keep only one
3768 : : * We must keep one NULL input because OR expressions evaluate to NULL when no
3769 : : * input is TRUE and at least one is NULL. We don't actually include the NULL
3770 : : * here, that's supposed to be done by the caller.
3771 : : *
3772 : : * The output arguments *haveNull and *forceTrue must be initialized false
3773 : : * by the caller. They will be set true if a NULL constant or TRUE constant,
3774 : : * respectively, is detected anywhere in the argument list.
3775 : : */
3776 : : static List *
6931 tgl@sss.pgh.pa.us 3777 :CBC 6188 : simplify_or_arguments(List *args,
3778 : : eval_const_expressions_context *context,
3779 : : bool *haveNull, bool *forceTrue)
3780 : : {
7398 3781 : 6188 : List *newargs = NIL;
3782 : : List *unprocessed_args;
3783 : :
3784 : : /*
3785 : : * We want to ensure that any OR immediately beneath another OR gets
3786 : : * flattened into a single OR-list, so as to simplify later reasoning.
3787 : : *
3788 : : * To avoid stack overflow from recursion of eval_const_expressions, we
3789 : : * resort to some tenseness here: we keep a list of not-yet-processed
3790 : : * inputs, and handle flattening of nested ORs by prepending to the to-do
3791 : : * list instead of recursing. Now that the parser generates N-argument
3792 : : * ORs from simple lists, this complexity is probably less necessary than
3793 : : * it once was, but we might as well keep the logic.
3794 : : */
6931 3795 : 6188 : unprocessed_args = list_copy(args);
3796 [ + + ]: 20719 : while (unprocessed_args)
3797 : : {
3798 : 14603 : Node *arg = (Node *) linitial(unprocessed_args);
3799 : :
3800 : 14603 : unprocessed_args = list_delete_first(unprocessed_args);
3801 : :
3802 : : /* flatten nested ORs as per above comment */
1902 3803 [ + + ]: 14603 : if (is_orclause(arg))
6931 3804 : 3 : {
1707 3805 : 3 : List *subargs = ((BoolExpr *) arg)->args;
3806 : 3 : List *oldlist = unprocessed_args;
3807 : :
3808 : 3 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
3809 : : /* perhaps-overly-tense code to avoid leaking old lists */
3810 : 3 : list_free(oldlist);
6931 3811 : 3 : continue;
3812 : : }
3813 : :
3814 : : /* If it's not an OR, simplify it */
3815 : 14600 : arg = eval_const_expressions_mutator(arg, context);
3816 : :
3817 : : /*
3818 : : * It is unlikely but not impossible for simplification of a non-OR
3819 : : * clause to produce an OR. Recheck, but don't be too tense about it
3820 : : * since it's not a mainstream case. In particular we don't worry
3821 : : * about const-simplifying the input twice, nor about list leakage.
3822 : : */
1902 3823 [ - + ]: 14600 : if (is_orclause(arg))
6931 tgl@sss.pgh.pa.us 3824 :UBC 0 : {
1707 3825 : 0 : List *subargs = ((BoolExpr *) arg)->args;
3826 : :
3827 : 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
6931 3828 : 0 : continue;
3829 : : }
3830 : :
3831 : : /*
3832 : : * OK, we have a const-simplified non-OR argument. Process it per
3833 : : * comments above.
3834 : : */
7398 tgl@sss.pgh.pa.us 3835 [ + + ]:CBC 14600 : if (IsA(arg, Const))
3836 : 69 : {
7168 bruce@momjian.us 3837 : 141 : Const *const_input = (Const *) arg;
3838 : :
7398 tgl@sss.pgh.pa.us 3839 [ + + ]: 141 : if (const_input->constisnull)
3840 : 24 : *haveNull = true;
3841 [ + + ]: 117 : else if (DatumGetBool(const_input->constvalue))
3842 : : {
3843 : 72 : *forceTrue = true;
3844 : :
3845 : : /*
3846 : : * Once we detect a TRUE result we can just exit the loop
3847 : : * immediately. However, if we ever add a notion of
3848 : : * non-removable functions, we'd need to keep scanning.
3849 : : */
3850 : 72 : return NIL;
3851 : : }
3852 : : /* otherwise, we can drop the constant-false input */
6931 3853 : 69 : continue;
3854 : : }
3855 : :
3856 : : /* else emit the simplified arg into the result list */
3857 : 14459 : newargs = lappend(newargs, arg);
3858 : : }
3859 : :
7398 3860 : 6116 : return newargs;
3861 : : }
3862 : :
3863 : : /*
3864 : : * Subroutine for eval_const_expressions: process arguments of an AND clause
3865 : : *
3866 : : * This includes flattening of nested ANDs as well as recursion to
3867 : : * eval_const_expressions to simplify the AND arguments.
3868 : : *
3869 : : * After simplification, AND arguments are handled as follows:
3870 : : * non constant: keep
3871 : : * TRUE: drop (does not affect result)
3872 : : * FALSE: force result to FALSE
3873 : : * NULL: keep only one
3874 : : * We must keep one NULL input because AND expressions evaluate to NULL when
3875 : : * no input is FALSE and at least one is NULL. We don't actually include the
3876 : : * NULL here, that's supposed to be done by the caller.
3877 : : *
3878 : : * The output arguments *haveNull and *forceFalse must be initialized false
3879 : : * by the caller. They will be set true if a null constant or false constant,
3880 : : * respectively, is detected anywhere in the argument list.
3881 : : */
3882 : : static List *
6931 3883 : 60788 : simplify_and_arguments(List *args,
3884 : : eval_const_expressions_context *context,
3885 : : bool *haveNull, bool *forceFalse)
3886 : : {
7398 3887 : 60788 : List *newargs = NIL;
3888 : : List *unprocessed_args;
3889 : :
3890 : : /* See comments in simplify_or_arguments */
6931 3891 : 60788 : unprocessed_args = list_copy(args);
3892 [ + + ]: 223951 : while (unprocessed_args)
3893 : : {
3894 : 163896 : Node *arg = (Node *) linitial(unprocessed_args);
3895 : :
3896 : 163896 : unprocessed_args = list_delete_first(unprocessed_args);
3897 : :
3898 : : /* flatten nested ANDs as per above comment */
1902 3899 [ + + ]: 163896 : if (is_andclause(arg))
6931 3900 : 560 : {
1707 3901 : 560 : List *subargs = ((BoolExpr *) arg)->args;
3902 : 560 : List *oldlist = unprocessed_args;
3903 : :
3904 : 560 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
3905 : : /* perhaps-overly-tense code to avoid leaking old lists */
3906 : 560 : list_free(oldlist);
6931 3907 : 560 : continue;
3908 : : }
3909 : :
3910 : : /* If it's not an AND, simplify it */
3911 : 163336 : arg = eval_const_expressions_mutator(arg, context);
3912 : :
3913 : : /*
3914 : : * It is unlikely but not impossible for simplification of a non-AND
3915 : : * clause to produce an AND. Recheck, but don't be too tense about it
3916 : : * since it's not a mainstream case. In particular we don't worry
3917 : : * about const-simplifying the input twice, nor about list leakage.
3918 : : */
1902 3919 [ + + ]: 163336 : if (is_andclause(arg))
6931 3920 : 15 : {
1707 3921 : 15 : List *subargs = ((BoolExpr *) arg)->args;
3922 : :
3923 : 15 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
6931 3924 : 15 : continue;
3925 : : }
3926 : :
3927 : : /*
3928 : : * OK, we have a const-simplified non-AND argument. Process it per
3929 : : * comments above.
3930 : : */
7398 3931 [ + + ]: 163321 : if (IsA(arg, Const))
3932 : 836 : {
7168 bruce@momjian.us 3933 : 1569 : Const *const_input = (Const *) arg;
3934 : :
7398 tgl@sss.pgh.pa.us 3935 [ + + ]: 1569 : if (const_input->constisnull)
3936 : 9 : *haveNull = true;
3937 [ + + ]: 1560 : else if (!DatumGetBool(const_input->constvalue))
3938 : : {
3939 : 733 : *forceFalse = true;
3940 : :
3941 : : /*
3942 : : * Once we detect a FALSE result we can just exit the loop
3943 : : * immediately. However, if we ever add a notion of
3944 : : * non-removable functions, we'd need to keep scanning.
3945 : : */
3946 : 733 : return NIL;
3947 : : }
3948 : : /* otherwise, we can drop the constant-true input */
6931 3949 : 836 : continue;
3950 : : }
3951 : :
3952 : : /* else emit the simplified arg into the result list */
3953 : 161752 : newargs = lappend(newargs, arg);
3954 : : }
3955 : :
7398 3956 : 60055 : return newargs;
3957 : : }
3958 : :
3959 : : /*
3960 : : * Subroutine for eval_const_expressions: try to simplify boolean equality
3961 : : * or inequality condition
3962 : : *
3963 : : * Inputs are the operator OID and the simplified arguments to the operator.
3964 : : * Returns a simplified expression if successful, or NULL if cannot
3965 : : * simplify the expression.
3966 : : *
3967 : : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
3968 : : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
3969 : : * This is only marginally useful in itself, but doing it in constant folding
3970 : : * ensures that we will recognize these forms as being equivalent in, for
3971 : : * example, partial index matching.
3972 : : *
3973 : : * We come here only if simplify_function has failed; therefore we cannot
3974 : : * see two constant inputs, nor a constant-NULL input.
3975 : : */
3976 : : static Node *
5382 3977 : 278 : simplify_boolean_equality(Oid opno, List *args)
3978 : : {
3979 : : Node *leftop;
3980 : : Node *rightop;
3981 : :
6958 3982 [ - + ]: 278 : Assert(list_length(args) == 2);
3983 : 278 : leftop = linitial(args);
3984 : 278 : rightop = lsecond(args);
3985 [ + - - + ]: 278 : if (leftop && IsA(leftop, Const))
3986 : : {
6958 tgl@sss.pgh.pa.us 3987 [ # # ]:UBC 0 : Assert(!((Const *) leftop)->constisnull);
5382 3988 [ # # ]: 0 : if (opno == BooleanEqualOperator)
3989 : : {
3990 [ # # ]: 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
5161 bruce@momjian.us 3991 : 0 : return rightop; /* true = foo */
3992 : : else
4753 3993 : 0 : return negate_clause(rightop); /* false = foo */
3994 : : }
3995 : : else
3996 : : {
5382 tgl@sss.pgh.pa.us 3997 [ # # ]: 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4753 bruce@momjian.us 3998 : 0 : return negate_clause(rightop); /* true <> foo */
3999 : : else
5161 4000 : 0 : return rightop; /* false <> foo */
4001 : : }
4002 : : }
6958 tgl@sss.pgh.pa.us 4003 [ + - + + ]:CBC 278 : if (rightop && IsA(rightop, Const))
4004 : : {
4005 [ - + ]: 189 : Assert(!((Const *) rightop)->constisnull);
5382 4006 [ + + ]: 189 : if (opno == BooleanEqualOperator)
4007 : : {
4008 [ + + ]: 156 : if (DatumGetBool(((Const *) rightop)->constvalue))
5161 bruce@momjian.us 4009 : 75 : return leftop; /* foo = true */
4010 : : else
4935 tgl@sss.pgh.pa.us 4011 : 81 : return negate_clause(leftop); /* foo = false */
4012 : : }
4013 : : else
4014 : : {
5382 4015 [ + + ]: 33 : if (DatumGetBool(((Const *) rightop)->constvalue))
4935 4016 : 30 : return negate_clause(leftop); /* foo <> true */
4017 : : else
5161 bruce@momjian.us 4018 : 3 : return leftop; /* foo <> false */
4019 : : }
4020 : : }
6958 tgl@sss.pgh.pa.us 4021 : 89 : return NULL;
4022 : : }
4023 : :
4024 : : /*
4025 : : * Subroutine for eval_const_expressions: try to simplify a function call
4026 : : * (which might originally have been an operator; we don't care)
4027 : : *
4028 : : * Inputs are the function OID, actual result type OID (which is needed for
4029 : : * polymorphic functions), result typmod, result collation, the input
4030 : : * collation to use for the function, the original argument list (not
4031 : : * const-simplified yet, unless process_args is false), and some flags;
4032 : : * also the context data for eval_const_expressions.
4033 : : *
4034 : : * Returns a simplified expression if successful, or NULL if cannot
4035 : : * simplify the function call.
4036 : : *
4037 : : * This function is also responsible for converting named-notation argument
4038 : : * lists into positional notation and/or adding any needed default argument
4039 : : * expressions; which is a bit grotty, but it avoids extra fetches of the
4040 : : * function's pg_proc tuple. For this reason, the args list is
4041 : : * pass-by-reference. Conversion and const-simplification of the args list
4042 : : * will be done even if simplification of the function call itself is not
4043 : : * possible.
4044 : : */
4045 : : static Expr *
4405 4046 : 581439 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4047 : : Oid result_collid, Oid input_collid, List **args_p,
4048 : : bool funcvariadic, bool process_args, bool allow_non_const,
4049 : : eval_const_expressions_context *context)
4050 : : {
4051 : 581439 : List *args = *args_p;
4052 : : HeapTuple func_tuple;
4053 : : Form_pg_proc func_form;
4054 : : Expr *newexpr;
4055 : :
4056 : : /*
4057 : : * We have three strategies for simplification: execute the function to
4058 : : * deliver a constant result, use a transform function to generate a
4059 : : * substitute node tree, or expand in-line the body of the function
4060 : : * definition (which only works for simple SQL-language functions, but
4061 : : * that is a common case). Each case needs access to the function's
4062 : : * pg_proc tuple, so fetch it just once.
4063 : : *
4064 : : * Note: the allow_non_const flag suppresses both the second and third
4065 : : * strategies; so if !allow_non_const, simplify_function can only return a
4066 : : * Const or NULL. Argument-list rewriting happens anyway, though.
4067 : : */
5173 rhaas@postgresql.org 4068 : 581439 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
8792 tgl@sss.pgh.pa.us 4069 [ - + ]: 581439 : if (!HeapTupleIsValid(func_tuple))
7569 tgl@sss.pgh.pa.us 4070 [ # # ]:UBC 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4405 tgl@sss.pgh.pa.us 4071 :CBC 581439 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4072 : :
4073 : : /*
4074 : : * Process the function arguments, unless the caller did it already.
4075 : : *
4076 : : * Here we must deal with named or defaulted arguments, and then
4077 : : * recursively apply eval_const_expressions to the whole argument list.
4078 : : */
4079 [ + + ]: 581439 : if (process_args)
4080 : : {
1039 4081 : 580418 : args = expand_function_arguments(args, false, result_type, func_tuple);
4405 4082 : 580418 : args = (List *) expression_tree_mutator((Node *) args,
4083 : : eval_const_expressions_mutator,
4084 : : (void *) context);
4085 : : /* Argument processing done, give it back to the caller */
4086 : 580357 : *args_p = args;
4087 : : }
4088 : :
4089 : : /* Now attempt simplification of the function call proper. */
4090 : :
4775 4091 : 581378 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4092 : : result_collid, input_collid,
4093 : : args, funcvariadic,
4094 : : func_tuple, context);
4095 : :
1891 4096 [ + + + - : 579584 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
+ + ]
4097 : : {
4098 : : /*
4099 : : * Build a SupportRequestSimplify node to pass to the support
4100 : : * function, pointing to a dummy FuncExpr node containing the
4101 : : * simplified arg list. We use this approach to present a uniform
4102 : : * interface to the support function regardless of how the target
4103 : : * function is actually being invoked.
4104 : : */
4105 : : SupportRequestSimplify req;
4106 : : FuncExpr fexpr;
4107 : :
4405 4108 : 14983 : fexpr.xpr.type = T_FuncExpr;
4109 : 14983 : fexpr.funcid = funcid;
4110 : 14983 : fexpr.funcresulttype = result_type;
4111 : 14983 : fexpr.funcretset = func_form->proretset;
4101 4112 : 14983 : fexpr.funcvariadic = funcvariadic;
4202 4113 : 14983 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4405 4114 : 14983 : fexpr.funccollid = result_collid;
4115 : 14983 : fexpr.inputcollid = input_collid;
4116 : 14983 : fexpr.args = args;
4117 : 14983 : fexpr.location = -1;
4118 : :
1891 4119 : 14983 : req.type = T_SupportRequestSimplify;
4120 : 14983 : req.root = context->root;
4121 : 14983 : req.fcall = &fexpr;
4122 : :
4123 : : newexpr = (Expr *)
4124 : 14983 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4125 : : PointerGetDatum(&req)));
4126 : :
4127 : : /* catch a possible API misunderstanding */
4128 [ - + ]: 14983 : Assert(newexpr != (Expr *) &fexpr);
4129 : : }
4130 : :
4405 4131 [ + + + - ]: 579584 : if (!newexpr && allow_non_const)
4769 4132 : 493756 : newexpr = inline_function(funcid, result_type, result_collid,
4133 : : input_collid, args, funcvariadic,
4134 : : func_tuple, context);
4135 : :
8550 4136 : 579574 : ReleaseSysCache(func_tuple);
4137 : :
7805 4138 : 579574 : return newexpr;
4139 : : }
4140 : :
4141 : : /*
4142 : : * expand_function_arguments: convert named-notation args to positional args
4143 : : * and/or insert default args, as needed
4144 : : *
4145 : : * Returns a possibly-transformed version of the args list.
4146 : : *
4147 : : * If include_out_arguments is true, then the args list and the result
4148 : : * include OUT arguments.
4149 : : *
4150 : : * The expected result type of the call must be given, for sanity-checking
4151 : : * purposes. Also, we ask the caller to provide the function's actual
4152 : : * pg_proc tuple, not just its OID.
4153 : : *
4154 : : * If we need to change anything, the input argument list is copied, not
4155 : : * modified.
4156 : : *
4157 : : * Note: this gets applied to operator argument lists too, even though the
4158 : : * cases it handles should never occur there. This should be OK since it
4159 : : * will fall through very quickly if there's nothing to do.
4160 : : */
4161 : : List *
1039 4162 : 582271 : expand_function_arguments(List *args, bool include_out_arguments,
4163 : : Oid result_type, HeapTuple func_tuple)
4164 : : {
4405 4165 : 582271 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
1039 4166 : 582271 : Oid *proargtypes = funcform->proargtypes.values;
4167 : 582271 : int pronargs = funcform->pronargs;
4405 4168 : 582271 : bool has_named_args = false;
4169 : : ListCell *lc;
4170 : :
4171 : : /*
4172 : : * If we are asked to match to OUT arguments, then use the proallargtypes
4173 : : * array (which includes those); otherwise use proargtypes (which
4174 : : * doesn't). Of course, if proallargtypes is null, we always use
4175 : : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4176 : : * considering that we may have nothing to do here, but fortunately the
4177 : : * common case is include_out_arguments == false.)
4178 : : */
1039 4179 [ + + ]: 582271 : if (include_out_arguments)
4180 : : {
4181 : : Datum proallargtypes;
4182 : : bool isNull;
4183 : :
4184 : 208 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4185 : : Anum_pg_proc_proallargtypes,
4186 : : &isNull);
4187 [ + + ]: 208 : if (!isNull)
4188 : : {
4189 : 81 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4190 : :
4191 : 81 : pronargs = ARR_DIMS(arr)[0];
4192 [ + - + - ]: 81 : if (ARR_NDIM(arr) != 1 ||
4193 : 81 : pronargs < 0 ||
4194 [ + - ]: 81 : ARR_HASNULL(arr) ||
4195 [ - + ]: 81 : ARR_ELEMTYPE(arr) != OIDOID)
1039 tgl@sss.pgh.pa.us 4196 [ # # ]:UBC 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
1039 tgl@sss.pgh.pa.us 4197 [ - + ]:CBC 81 : Assert(pronargs >= funcform->pronargs);
4198 [ - + ]: 81 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4199 : : }
4200 : : }
4201 : :
4202 : : /* Do we have any named arguments? */
4405 4203 [ + + + + : 1527470 : foreach(lc, args)
+ + ]
4204 : : {
4205 : 953126 : Node *arg = (Node *) lfirst(lc);
4206 : :
4207 [ + + ]: 953126 : if (IsA(arg, NamedArgExpr))
4208 : : {
4209 : 7927 : has_named_args = true;
4210 : 7927 : break;
4211 : : }
4212 : : }
4213 : :
4214 : : /* If so, we must apply reorder_function_arguments */
4215 [ + + ]: 582271 : if (has_named_args)
4216 : : {
1039 4217 : 7927 : args = reorder_function_arguments(args, pronargs, func_tuple);
4218 : : /* Recheck argument types and add casts if needed */
4219 : 7927 : recheck_cast_function_args(args, result_type,
4220 : : proargtypes, pronargs,
4221 : : func_tuple);
4222 : : }
4223 [ + + ]: 574344 : else if (list_length(args) < pronargs)
4224 : : {
4225 : : /* No named args, but we seem to be short some defaults */
4226 : 2894 : args = add_function_defaults(args, pronargs, func_tuple);
4227 : : /* Recheck argument types and add casts if needed */
4228 : 2894 : recheck_cast_function_args(args, result_type,
4229 : : proargtypes, pronargs,
4230 : : func_tuple);
4231 : : }
4232 : :
4405 4233 : 582271 : return args;
4234 : : }
4235 : :
4236 : : /*
4237 : : * reorder_function_arguments: convert named-notation args to positional args
4238 : : *
4239 : : * This function also inserts default argument values as needed, since it's
4240 : : * impossible to form a truly valid positional call without that.
4241 : : */
4242 : : static List *
1039 4243 : 7927 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
4244 : : {
5302 4245 : 7927 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4246 : 7927 : int nargsprovided = list_length(args);
4247 : : Node *argarray[FUNC_MAX_ARGS];
4248 : : ListCell *lc;
4249 : : int i;
4250 : :
4251 [ - + ]: 7927 : Assert(nargsprovided <= pronargs);
1172 4252 [ + - - + ]: 7927 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
5302 tgl@sss.pgh.pa.us 4253 [ # # ]:UBC 0 : elog(ERROR, "too many function arguments");
1172 tgl@sss.pgh.pa.us 4254 :CBC 7927 : memset(argarray, 0, pronargs * sizeof(Node *));
4255 : :
4256 : : /* Deconstruct the argument list into an array indexed by argnumber */
5302 4257 : 7927 : i = 0;
4258 [ + - + + : 32199 : foreach(lc, args)
+ + ]
4259 : : {
5161 bruce@momjian.us 4260 : 24272 : Node *arg = (Node *) lfirst(lc);
4261 : :
5302 tgl@sss.pgh.pa.us 4262 [ + + ]: 24272 : if (!IsA(arg, NamedArgExpr))
4263 : : {
4264 : : /* positional argument, assumed to precede all named args */
4265 [ - + ]: 925 : Assert(argarray[i] == NULL);
4266 : 925 : argarray[i++] = arg;
4267 : : }
4268 : : else
4269 : : {
4270 : 23347 : NamedArgExpr *na = (NamedArgExpr *) arg;
4271 : :
1039 4272 [ + - - + ]: 23347 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
5302 4273 [ - + ]: 23347 : Assert(argarray[na->argnumber] == NULL);
4274 : 23347 : argarray[na->argnumber] = (Node *) na->arg;
4275 : : }
4276 : : }
4277 : :
4278 : : /*
4279 : : * Fetch default expressions, if needed, and insert into array at proper
4280 : : * locations (they aren't necessarily consecutive or all used)
4281 : : */
4282 [ + + ]: 7927 : if (nargsprovided < pronargs)
4283 : : {
5161 bruce@momjian.us 4284 : 3645 : List *defaults = fetch_function_defaults(func_tuple);
4285 : :
5302 tgl@sss.pgh.pa.us 4286 : 3645 : i = pronargs - funcform->pronargdefaults;
4287 [ + - + + : 20889 : foreach(lc, defaults)
+ + ]
4288 : : {
4289 [ + + ]: 17244 : if (argarray[i] == NULL)
4290 : 7228 : argarray[i] = (Node *) lfirst(lc);
4291 : 17244 : i++;
4292 : : }
4293 : : }
4294 : :
4295 : : /* Now reconstruct the args list in proper order */
4296 : 7927 : args = NIL;
4297 [ + + ]: 39427 : for (i = 0; i < pronargs; i++)
4298 : : {
4299 [ - + ]: 31500 : Assert(argarray[i] != NULL);
4300 : 31500 : args = lappend(args, argarray[i]);
4301 : : }
4302 : :
4303 : 7927 : return args;
4304 : : }
4305 : :
4306 : : /*
4307 : : * add_function_defaults: add missing function arguments from its defaults
4308 : : *
4309 : : * This is used only when the argument list was positional to begin with,
4310 : : * and so we know we just need to add defaults at the end.
4311 : : */
4312 : : static List *
1039 4313 : 2894 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
4314 : : {
5577 4315 : 2894 : int nargsprovided = list_length(args);
4316 : : List *defaults;
4317 : : int ndelete;
4318 : :
4319 : : /* Get all the default expressions from the pg_proc tuple */
5302 4320 : 2894 : defaults = fetch_function_defaults(func_tuple);
4321 : :
4322 : : /* Delete any unused defaults from the list */
1039 4323 : 2894 : ndelete = nargsprovided + list_length(defaults) - pronargs;
5596 4324 [ - + ]: 2894 : if (ndelete < 0)
5596 tgl@sss.pgh.pa.us 4325 [ # # ]:UBC 0 : elog(ERROR, "not enough default arguments");
1733 tgl@sss.pgh.pa.us 4326 [ + + ]:CBC 2894 : if (ndelete > 0)
894 4327 : 114 : defaults = list_delete_first_n(defaults, ndelete);
4328 : :
4329 : : /* And form the combined argument list, not modifying the input list */
1707 4330 : 2894 : return list_concat_copy(args, defaults);
4331 : : }
4332 : :
4333 : : /*
4334 : : * fetch_function_defaults: get function's default arguments as expression list
4335 : : */
4336 : : static List *
5302 4337 : 6539 : fetch_function_defaults(HeapTuple func_tuple)
4338 : : {
4339 : : List *defaults;
4340 : : Datum proargdefaults;
4341 : : char *str;
4342 : :
386 dgustafsson@postgres 4343 : 6539 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
4344 : : Anum_pg_proc_proargdefaults);
5302 tgl@sss.pgh.pa.us 4345 : 6539 : str = TextDatumGetCString(proargdefaults);
2609 peter_e@gmx.net 4346 : 6539 : defaults = castNode(List, stringToNode(str));
5302 tgl@sss.pgh.pa.us 4347 : 6539 : pfree(str);
4348 : 6539 : return defaults;
4349 : : }
4350 : :
4351 : : /*
4352 : : * recheck_cast_function_args: recheck function args and typecast as needed
4353 : : * after adding defaults.
4354 : : *
4355 : : * It is possible for some of the defaulted arguments to be polymorphic;
4356 : : * therefore we can't assume that the default expressions have the correct
4357 : : * data types already. We have to re-resolve polymorphics and do coercion
4358 : : * just like the parser did.
4359 : : *
4360 : : * This should be a no-op if there are no polymorphic arguments,
4361 : : * but we do it anyway to be sure.
4362 : : *
4363 : : * Note: if any casts are needed, the args list is modified in-place;
4364 : : * caller should have already copied the list structure.
4365 : : */
4366 : : static void
1039 4367 : 10821 : recheck_cast_function_args(List *args, Oid result_type,
4368 : : Oid *proargtypes, int pronargs,
4369 : : HeapTuple func_tuple)
4370 : : {
5302 4371 : 10821 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4372 : : int nargs;
4373 : : Oid actual_arg_types[FUNC_MAX_ARGS];
4374 : : Oid declared_arg_types[FUNC_MAX_ARGS];
4375 : : Oid rettype;
4376 : : ListCell *lc;
4377 : :
5596 4378 [ - + ]: 10821 : if (list_length(args) > FUNC_MAX_ARGS)
5596 tgl@sss.pgh.pa.us 4379 [ # # ]:UBC 0 : elog(ERROR, "too many function arguments");
5596 tgl@sss.pgh.pa.us 4380 :CBC 10821 : nargs = 0;
4381 [ + - + + : 53224 : foreach(lc, args)
+ + ]
4382 : : {
4383 : 42403 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
4384 : : }
1039 4385 [ - + ]: 10821 : Assert(nargs == pronargs);
4386 : 10821 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
5596 4387 : 10821 : rettype = enforce_generic_type_consistency(actual_arg_types,
4388 : : declared_arg_types,
4389 : : nargs,
4390 : : funcform->prorettype,
4391 : : false);
4392 : : /* let's just check we got the same answer as the parser did ... */
4393 [ - + ]: 10821 : if (rettype != result_type)
5596 tgl@sss.pgh.pa.us 4394 [ # # ]:UBC 0 : elog(ERROR, "function's resolved result type changed during planning");
4395 : :
4396 : : /* perform any necessary typecasting of arguments */
5596 tgl@sss.pgh.pa.us 4397 :CBC 10821 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
4398 : 10821 : }
4399 : :
4400 : : /*
4401 : : * evaluate_function: try to pre-evaluate a function call
4402 : : *
4403 : : * We can do this if the function is strict and has any constant-null inputs
4404 : : * (just return a null constant), or if the function is immutable and has all
4405 : : * constant inputs (call it and return the result as a Const node). In
4406 : : * estimation mode we are willing to pre-evaluate stable functions too.
4407 : : *
4408 : : * Returns a simplified expression if successful, or NULL if cannot
4409 : : * simplify the function.
4410 : : */
4411 : : static Expr *
4775 4412 : 581378 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
4413 : : Oid result_collid, Oid input_collid, List *args,
4414 : : bool funcvariadic,
4415 : : HeapTuple func_tuple,
4416 : : eval_const_expressions_context *context)
4417 : : {
7805 4418 : 581378 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4419 : 581378 : bool has_nonconst_input = false;
4420 : 581378 : bool has_null_input = false;
4421 : : ListCell *arg;
4422 : : FuncExpr *newexpr;
4423 : :
4424 : : /*
4425 : : * Can't simplify if it returns a set.
4426 : : */
4427 [ + + ]: 581378 : if (funcform->proretset)
8792 4428 : 28247 : return NULL;
4429 : :
4430 : : /*
4431 : : * Can't simplify if it returns RECORD. The immediate problem is that it
4432 : : * will be needing an expected tupdesc which we can't supply here.
4433 : : *
4434 : : * In the case where it has OUT parameters, it could get by without an
4435 : : * expected tupdesc, but we still have issues: get_expr_result_type()
4436 : : * doesn't know how to extract type info from a RECORD constant, and in
4437 : : * the case of a NULL function result there doesn't seem to be any clean
4438 : : * way to fix that. In view of the likelihood of there being still other
4439 : : * gotchas, seems best to leave the function call unreduced.
4440 : : */
6860 4441 [ + + ]: 553131 : if (funcform->prorettype == RECORDOID)
6940 4442 : 1956 : return NULL;
4443 : :
4444 : : /*
4445 : : * Check for constant inputs and especially constant-NULL inputs.
4446 : : */
7805 4447 [ + + + + : 1453914 : foreach(arg, args)
+ + ]
4448 : : {
4449 [ + + ]: 902739 : if (IsA(lfirst(arg), Const))
4450 : 384623 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
4451 : : else
4452 : 518116 : has_nonconst_input = true;
4453 : : }
4454 : :
4455 : : /*
4456 : : * If the function is strict and has a constant-NULL input, it will never
4457 : : * be called at all, so we can replace the call by a NULL constant, even
4458 : : * if there are other inputs that aren't constant, and even if the
4459 : : * function is not otherwise immutable.
4460 : : */
4461 [ + + + + ]: 551175 : if (funcform->proisstrict && has_null_input)
4769 4462 : 312 : return (Expr *) makeNullConst(result_type, result_typmod,
4463 : : result_collid);
4464 : :
4465 : : /*
4466 : : * Otherwise, can simplify only if all inputs are constants. (For a
4467 : : * non-strict function, constant NULL inputs are treated the same as
4468 : : * constant non-NULL inputs.)
4469 : : */
7096 4470 [ + + ]: 550863 : if (has_nonconst_input)
4471 : 388229 : return NULL;
4472 : :
4473 : : /*
4474 : : * Ordinarily we are only allowed to simplify immutable functions. But for
4475 : : * purposes of estimation, we consider it okay to simplify functions that
4476 : : * are merely stable; the risk that the result might change from planning
4477 : : * time to execution time is worth taking in preference to not being able
4478 : : * to estimate the value at all.
4479 : : */
4480 [ + + ]: 162634 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
4481 : : /* okay */ ;
4482 [ + + + + ]: 76704 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
4483 : : /* okay */ ;
4484 : : else
8722 4485 : 75387 : return NULL;
4486 : :
4487 : : /*
4488 : : * OK, looks like we can simplify this operator/function.
4489 : : *
4490 : : * Build a new FuncExpr node containing the already-simplified arguments.
4491 : : */
7794 4492 : 87247 : newexpr = makeNode(FuncExpr);
4493 : 87247 : newexpr->funcid = funcid;
7677 4494 : 87247 : newexpr->funcresulttype = result_type;
7794 4495 : 87247 : newexpr->funcretset = false;
4101 4496 : 87247 : newexpr->funcvariadic = funcvariadic;
3973 bruce@momjian.us 4497 : 87247 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
2489 tgl@sss.pgh.pa.us 4498 : 87247 : newexpr->funccollid = result_collid; /* doesn't matter */
4775 4499 : 87247 : newexpr->inputcollid = input_collid;
8792 4500 : 87247 : newexpr->args = args;
5708 4501 : 87247 : newexpr->location = -1;
4502 : :
4769 4503 : 87247 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
4504 : : result_collid);
4505 : : }
4506 : :
4507 : : /*
4508 : : * inline_function: try to expand a function call inline
4509 : : *
4510 : : * If the function is a sufficiently simple SQL-language function
4511 : : * (just "SELECT expression"), then we can inline it and avoid the rather
4512 : : * high per-call overhead of SQL functions. Furthermore, this can expose
4513 : : * opportunities for constant-folding within the function expression.
4514 : : *
4515 : : * We have to beware of some special cases however. A directly or
4516 : : * indirectly recursive function would cause us to recurse forever,
4517 : : * so we keep track of which functions we are already expanding and
4518 : : * do not re-expand them. Also, if a parameter is used more than once
4519 : : * in the SQL-function body, we require it not to contain any volatile
4520 : : * functions (volatiles might deliver inconsistent answers) nor to be
4521 : : * unreasonably expensive to evaluate. The expensiveness check not only
4522 : : * prevents us from doing multiple evaluations of an expensive parameter
4523 : : * at runtime, but is a safety value to limit growth of an expression due
4524 : : * to repeated inlining.
4525 : : *
4526 : : * We must also beware of changing the volatility or strictness status of
4527 : : * functions by inlining them.
4528 : : *
4529 : : * Also, at the moment we can't inline functions returning RECORD. This
4530 : : * doesn't work in the general case because it discards information such
4531 : : * as OUT-parameter declarations.
4532 : : *
4533 : : * Also, context-dependent expression nodes in the argument list are trouble.
4534 : : *
4535 : : * Returns a simplified expression if successful, or NULL if cannot
4536 : : * simplify the function.
4537 : : */
4538 : : static Expr *
4539 : 493756 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
4540 : : Oid input_collid, List *args,
4541 : : bool funcvariadic,
4542 : : HeapTuple func_tuple,
4543 : : eval_const_expressions_context *context)
4544 : : {
7805 4545 : 493756 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4546 : : char *src;
4547 : : Datum tmp;
4548 : : bool isNull;
4549 : : MemoryContext oldcxt;
4550 : : MemoryContext mycxt;
4551 : : inline_error_callback_arg callback_arg;
4552 : : ErrorContextCallback sqlerrcontext;
4553 : : FuncExpr *fexpr;
4554 : : SQLFunctionParseInfoPtr pinfo;
4555 : : TupleDesc rettupdesc;
4556 : : ParseState *pstate;
4557 : : List *raw_parsetree_list;
4558 : : List *querytree_list;
4559 : : Query *querytree;
4560 : : Node *newexpr;
4561 : : int *usecounts;
4562 : : ListCell *arg;
4563 : : int i;
4564 : :
4565 : : /*
4566 : : * Forget it if the function is not SQL-language or has other showstopper
4567 : : * properties. (The prokind and nargs checks are just paranoia.)
4568 : : */
4569 [ + + ]: 493756 : if (funcform->prolang != SQLlanguageId ||
2235 peter_e@gmx.net 4570 [ + - ]: 16293 : funcform->prokind != PROKIND_FUNCTION ||
2221 tgl@sss.pgh.pa.us 4571 [ + + ]: 16293 : funcform->prosecdef ||
7805 4572 [ + + ]: 16287 : funcform->proretset ||
4883 4573 [ + + ]: 15619 : funcform->prorettype == RECORDOID ||
2209 andrew@dunslane.net 4574 [ + + - + ]: 30923 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
7259 neilc@samurai.com 4575 : 15457 : funcform->pronargs != list_length(args))
7805 tgl@sss.pgh.pa.us 4576 : 478299 : return NULL;
4577 : :
4578 : : /* Check for recursive function, and give up trying to expand if so */
7247 4579 [ + + ]: 15457 : if (list_member_oid(context->active_fns, funcid))
7805 4580 : 4254 : return NULL;
4581 : :
4582 : : /* Check permission to call function (fail later, if not) */
518 peter@eisentraut.org 4583 [ + + ]: 11203 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
7805 tgl@sss.pgh.pa.us 4584 : 7 : return NULL;
4585 : :
4586 : : /* Check whether a plugin wants to hook function entry/exit */
4871 rhaas@postgresql.org 4587 [ - + - - ]: 11196 : if (FmgrHookIsNeeded(funcid))
4871 rhaas@postgresql.org 4588 :UBC 0 : return NULL;
4589 : :
4590 : : /*
4591 : : * Make a temporary memory context, so that we don't leak all the stuff
4592 : : * that parsing might create.
4593 : : */
7805 tgl@sss.pgh.pa.us 4594 :CBC 11196 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
4595 : : "inline_function",
4596 : : ALLOCSET_DEFAULT_SIZES);
4597 : 11196 : oldcxt = MemoryContextSwitchTo(mycxt);
4598 : :
4599 : : /*
4600 : : * We need a dummy FuncExpr node containing the already-simplified
4601 : : * arguments. (In some cases we don't really need it, but building it is
4602 : : * cheap enough that it's not worth contortions to avoid.)
4603 : : */
1055 4604 : 11196 : fexpr = makeNode(FuncExpr);
4605 : 11196 : fexpr->funcid = funcid;
4606 : 11196 : fexpr->funcresulttype = result_type;
4607 : 11196 : fexpr->funcretset = false;
4608 : 11196 : fexpr->funcvariadic = funcvariadic;
4609 : 11196 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
4610 : 11196 : fexpr->funccollid = result_collid; /* doesn't matter */
4611 : 11196 : fexpr->inputcollid = input_collid;
4612 : 11196 : fexpr->args = args;
4613 : 11196 : fexpr->location = -1;
4614 : :
4615 : : /* Fetch the function body */
386 dgustafsson@postgres 4616 : 11196 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
1095 tgl@sss.pgh.pa.us 4617 : 11196 : src = TextDatumGetCString(tmp);
4618 : :
4619 : : /*
4620 : : * Setup error traceback support for ereport(). This is so that we can
4621 : : * finger the function that bad information came from.
4622 : : */
5140 4623 : 11196 : callback_arg.proname = NameStr(funcform->proname);
1095 4624 : 11196 : callback_arg.prosrc = src;
4625 : :
5140 4626 : 11196 : sqlerrcontext.callback = sql_inline_error_callback;
4627 : 11196 : sqlerrcontext.arg = (void *) &callback_arg;
4628 : 11196 : sqlerrcontext.previous = error_context_stack;
4629 : 11196 : error_context_stack = &sqlerrcontext;
4630 : :
4631 : : /* If we have prosqlbody, pay attention to that not prosrc */
1103 peter@eisentraut.org 4632 : 11196 : tmp = SysCacheGetAttr(PROCOID,
4633 : : func_tuple,
4634 : : Anum_pg_proc_prosqlbody,
4635 : : &isNull);
1095 tgl@sss.pgh.pa.us 4636 [ + + ]: 11196 : if (!isNull)
4637 : : {
4638 : : Node *n;
4639 : : List *query_list;
4640 : :
1103 peter@eisentraut.org 4641 : 1446 : n = stringToNode(TextDatumGetCString(tmp));
4642 [ + + ]: 1446 : if (IsA(n, List))
557 drowley@postgresql.o 4643 : 1051 : query_list = linitial_node(List, castNode(List, n));
4644 : : else
4645 : 395 : query_list = list_make1(n);
4646 [ + + ]: 1446 : if (list_length(query_list) != 1)
1103 peter@eisentraut.org 4647 : 3 : goto fail;
557 drowley@postgresql.o 4648 : 1443 : querytree = linitial(query_list);
4649 : :
4650 : : /*
4651 : : * Because we'll insist below that the querytree have an empty rtable
4652 : : * and no sublinks, it cannot have any relation references that need
4653 : : * to be locked or rewritten. So we can omit those steps.
4654 : : */
4655 : : }
4656 : : else
4657 : : {
4658 : : /* Set up to handle parameters while parsing the function body. */
1068 tgl@sss.pgh.pa.us 4659 : 9750 : pinfo = prepare_sql_fn_parse_info(func_tuple,
4660 : : (Node *) fexpr,
4661 : : input_collid);
4662 : :
4663 : : /*
4664 : : * We just do parsing and parse analysis, not rewriting, because
4665 : : * rewriting will not affect table-free-SELECT-only queries, which is
4666 : : * all that we care about. Also, we can punt as soon as we detect
4667 : : * more than one command in the function body.
4668 : : */
4669 : 9750 : raw_parsetree_list = pg_parse_query(src);
4670 [ + + ]: 9750 : if (list_length(raw_parsetree_list) != 1)
4671 : 37 : goto fail;
4672 : :
4673 : 9713 : pstate = make_parsestate(NULL);
4674 : 9713 : pstate->p_sourcetext = src;
4675 : 9713 : sql_fn_parser_setup(pstate, pinfo);
4676 : :
4677 : 9713 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
4678 : :
4679 : 9707 : free_parsestate(pstate);
4680 : : }
4681 : :
4682 : : /*
4683 : : * The single command must be a simple "SELECT expression".
4684 : : *
4685 : : * Note: if you change the tests involved in this, see also plpgsql's
4686 : : * exec_simple_check_plan(). That generally needs to have the same idea
4687 : : * of what's a "simple expression", so that inlining a function that
4688 : : * previously wasn't inlined won't change plpgsql's conclusion.
4689 : : */
7805 4690 [ + - ]: 11150 : if (!IsA(querytree, Query) ||
4691 [ + + ]: 11150 : querytree->commandType != CMD_SELECT ||
4692 [ + + ]: 11087 : querytree->hasAggs ||
5586 4693 [ + - ]: 11048 : querytree->hasWindowFuncs ||
2770 4694 [ + - ]: 11048 : querytree->hasTargetSRFs ||
7805 4695 [ + + ]: 11048 : querytree->hasSubLinks ||
5671 4696 [ + - ]: 10730 : querytree->cteList ||
7805 4697 [ + + ]: 10730 : querytree->rtable ||
4698 [ + - ]: 9949 : querytree->jointree->fromlist ||
4699 [ + - ]: 9949 : querytree->jointree->quals ||
4700 [ + - ]: 9949 : querytree->groupClause ||
3256 andres@anarazel.de 4701 [ + - ]: 9949 : querytree->groupingSets ||
7805 tgl@sss.pgh.pa.us 4702 [ + - ]: 9949 : querytree->havingQual ||
5586 4703 [ + - ]: 9949 : querytree->windowClause ||
7805 4704 [ + - ]: 9949 : querytree->distinctClause ||
4705 [ + - ]: 9949 : querytree->sortClause ||
4706 [ + - ]: 9949 : querytree->limitOffset ||
4707 [ + + ]: 9949 : querytree->limitCount ||
4708 [ + - + + ]: 19824 : querytree->setOperations ||
7259 neilc@samurai.com 4709 : 9912 : list_length(querytree->targetList) != 1)
7805 tgl@sss.pgh.pa.us 4710 : 1268 : goto fail;
4711 : :
4712 : : /* If the function result is composite, resolve it */
1055 4713 : 9882 : (void) get_expr_result_type((Node *) fexpr,
4714 : : NULL,
4715 : : &rettupdesc);
4716 : :
4717 : : /*
4718 : : * Make sure the function (still) returns what it's declared to. This
4719 : : * will raise an error if wrong, but that's okay since the function would
4720 : : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
4721 : : * a coercion if needed to make the tlist expression match the declared
4722 : : * type of the function.
4723 : : *
4724 : : * Note: we do not try this until we have verified that no rewriting was
4725 : : * needed; that's probably not important, but let's be careful.
4726 : : */
1558 4727 : 9882 : querytree_list = list_make1(querytree);
1273 tgl@sss.pgh.pa.us 4728 [ + + ]:GNC 9882 : if (check_sql_fn_retval(list_make1(querytree_list),
4729 : : result_type, rettupdesc,
33 4730 : 9882 : funcform->prokind,
4731 : : false, NULL))
6249 tgl@sss.pgh.pa.us 4732 :CBC 6 : goto fail; /* reject whole-tuple-result cases */
4733 : :
4734 : : /*
4735 : : * Given the tests above, check_sql_fn_retval shouldn't have decided to
4736 : : * inject a projection step, but let's just make sure.
4737 : : */
1558 4738 [ - + ]: 9873 : if (querytree != linitial(querytree_list))
1558 tgl@sss.pgh.pa.us 4739 :UBC 0 : goto fail;
4740 : :
4741 : : /* Now we can grab the tlist expression */
5871 tgl@sss.pgh.pa.us 4742 :CBC 9873 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
4743 : :
4744 : : /*
4745 : : * If the SQL function returns VOID, we can only inline it if it is a
4746 : : * SELECT of an expression returning VOID (ie, it's just a redirection to
4747 : : * another VOID-returning function). In all non-VOID-returning cases,
4748 : : * check_sql_fn_retval should ensure that newexpr returns the function's
4749 : : * declared result type, so this test shouldn't fail otherwise; but we may
4750 : : * as well cope gracefully if it does.
4751 : : */
2221 4752 [ + + ]: 9873 : if (exprType(newexpr) != result_type)
4753 : 9 : goto fail;
4754 : :
4755 : : /*
4756 : : * Additional validity checks on the expression. It mustn't be more
4757 : : * volatile than the surrounding function (this is to avoid breaking hacks
4758 : : * that involve pretending a function is immutable when it really ain't).
4759 : : * If the surrounding function is declared strict, then the expression
4760 : : * must contain only strict constructs and must use all of the function
4761 : : * parameters (this is overkill, but an exact analysis is hard).
4762 : : */
7805 4763 [ + + + + ]: 10265 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
4764 : 401 : contain_mutable_functions(newexpr))
4765 : 6 : goto fail;
4766 [ + + - + ]: 10281 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
7559 bruce@momjian.us 4767 : 423 : contain_volatile_functions(newexpr))
7805 tgl@sss.pgh.pa.us 4768 :UBC 0 : goto fail;
4769 : :
7805 tgl@sss.pgh.pa.us 4770 [ + + + + ]:CBC 10698 : if (funcform->proisstrict &&
4771 : 840 : contain_nonstrict_functions(newexpr))
4772 : 86 : goto fail;
4773 : :
4774 : : /*
4775 : : * If any parameter expression contains a context-dependent node, we can't
4776 : : * inline, for fear of putting such a node into the wrong context.
4777 : : */
2806 4778 [ + + ]: 9772 : if (contain_context_dependent_node((Node *) args))
4779 : 3 : goto fail;
4780 : :
4781 : : /*
4782 : : * We may be able to do it; there are still checks on parameter usage to
4783 : : * make, but those are most easily done in combination with the actual
4784 : : * substitution of the inputs. So start building expression with inputs
4785 : : * substituted.
4786 : : */
7253 4787 : 9769 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
7805 4788 : 9769 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
4789 : : args, usecounts);
4790 : :
4791 : : /* Now check for parameter usage */
4792 : 9769 : i = 0;
4793 [ + + + + : 20256 : foreach(arg, args)
+ + ]
4794 : : {
7559 bruce@momjian.us 4795 : 10491 : Node *param = lfirst(arg);
4796 : :
7805 tgl@sss.pgh.pa.us 4797 [ + + ]: 10491 : if (usecounts[i] == 0)
4798 : : {
4799 : : /* Param not used at all: uncool if func is strict */
4800 [ - + ]: 82 : if (funcform->proisstrict)
7805 tgl@sss.pgh.pa.us 4801 :UBC 0 : goto fail;
4802 : : }
7805 tgl@sss.pgh.pa.us 4803 [ + + ]:CBC 10409 : else if (usecounts[i] != 1)
4804 : : {
4805 : : /* Param used multiple times: uncool if expensive or volatile */
4806 : : QualCost eval_cost;
4807 : :
4808 : : /*
4809 : : * We define "expensive" as "contains any subplan or more than 10
4810 : : * operators". Note that the subplan search has to be done
4811 : : * explicitly, since cost_qual_eval() will barf on unplanned
4812 : : * subselects.
4813 : : */
7560 4814 [ - + ]: 8231 : if (contain_subplans(param))
7560 tgl@sss.pgh.pa.us 4815 :UBC 0 : goto fail;
6261 tgl@sss.pgh.pa.us 4816 :CBC 8231 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
7560 4817 : 8231 : if (eval_cost.startup + eval_cost.per_tuple >
4818 [ - + ]: 8231 : 10 * cpu_operator_cost)
7560 tgl@sss.pgh.pa.us 4819 :UBC 0 : goto fail;
4820 : :
4821 : : /*
4822 : : * Check volatility last since this is more expensive than the
4823 : : * above tests
4824 : : */
7560 tgl@sss.pgh.pa.us 4825 [ + + ]:CBC 8231 : if (contain_volatile_functions(param))
7805 4826 : 4 : goto fail;
4827 : : }
4828 : 10487 : i++;
4829 : : }
4830 : :
4831 : : /*
4832 : : * Whew --- we can make the substitution. Copy the modified expression
4833 : : * out of the temporary memory context, and clean up.
4834 : : */
4835 : 9765 : MemoryContextSwitchTo(oldcxt);
4836 : :
4837 : 9765 : newexpr = copyObject(newexpr);
4838 : :
4839 : 9765 : MemoryContextDelete(mycxt);
4840 : :
4841 : : /*
4842 : : * If the result is of a collatable type, force the result to expose the
4843 : : * correct collation. In most cases this does not matter, but it's
4844 : : * possible that the function result is used directly as a sort key or in
4845 : : * other places where we expect exprCollation() to tell the truth.
4846 : : */
4769 4847 [ + + ]: 9765 : if (OidIsValid(result_collid))
4848 : : {
4753 bruce@momjian.us 4849 : 685 : Oid exprcoll = exprCollation(newexpr);
4850 : :
4769 tgl@sss.pgh.pa.us 4851 [ + - + + ]: 685 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
4852 : : {
4753 bruce@momjian.us 4853 : 18 : CollateExpr *newnode = makeNode(CollateExpr);
4854 : :
4770 tgl@sss.pgh.pa.us 4855 : 18 : newnode->arg = (Expr *) newexpr;
4769 4856 : 18 : newnode->collOid = result_collid;
4770 4857 : 18 : newnode->location = -1;
4858 : :
4859 : 18 : newexpr = (Node *) newnode;
4860 : : }
4861 : : }
4862 : :
4863 : : /*
4864 : : * Since there is now no trace of the function in the plan tree, we must
4865 : : * explicitly record the plan's dependency on the function.
4866 : : */
4607 4867 [ + + ]: 9765 : if (context->root)
4868 : 9694 : record_plan_function_dependency(context->root, funcid);
4869 : :
4870 : : /*
4871 : : * Recursively try to simplify the modified expression. Here we must add
4872 : : * the current function to the context list of active functions.
4873 : : */
1733 4874 : 9765 : context->active_fns = lappend_oid(context->active_fns, funcid);
7247 4875 : 9765 : newexpr = eval_const_expressions_mutator(newexpr, context);
1733 4876 : 9764 : context->active_fns = list_delete_last(context->active_fns);
4877 : :
7566 4878 : 9764 : error_context_stack = sqlerrcontext.previous;
4879 : :
7805 4880 : 9764 : return (Expr *) newexpr;
4881 : :
4882 : : /* Here if func is not inlinable: release temp memory and return NULL */
4883 : 1422 : fail:
4884 : 1422 : MemoryContextSwitchTo(oldcxt);
4885 : 1422 : MemoryContextDelete(mycxt);
7566 4886 : 1422 : error_context_stack = sqlerrcontext.previous;
4887 : :
7805 4888 : 1422 : return NULL;
4889 : : }
4890 : :
4891 : : /*
4892 : : * Replace Param nodes by appropriate actual parameters
4893 : : */
4894 : : static Node *
4895 : 9769 : substitute_actual_parameters(Node *expr, int nargs, List *args,
4896 : : int *usecounts)
4897 : : {
4898 : : substitute_actual_parameters_context context;
4899 : :
7559 bruce@momjian.us 4900 : 9769 : context.nargs = nargs;
7805 tgl@sss.pgh.pa.us 4901 : 9769 : context.args = args;
4902 : 9769 : context.usecounts = usecounts;
4903 : :
4904 : 9769 : return substitute_actual_parameters_mutator(expr, &context);
4905 : : }
4906 : :
4907 : : static Node *
4908 : 83389 : substitute_actual_parameters_mutator(Node *node,
4909 : : substitute_actual_parameters_context *context)
4910 : : {
4911 [ + + ]: 83389 : if (node == NULL)
4912 : 8530 : return NULL;
4913 [ + + ]: 74859 : if (IsA(node, Param))
4914 : : {
4915 : 19181 : Param *param = (Param *) node;
4916 : :
6567 4917 [ - + ]: 19181 : if (param->paramkind != PARAM_EXTERN)
6567 tgl@sss.pgh.pa.us 4918 [ # # ]:UBC 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
7805 tgl@sss.pgh.pa.us 4919 [ + - - + ]:CBC 19181 : if (param->paramid <= 0 || param->paramid > context->nargs)
7569 tgl@sss.pgh.pa.us 4920 [ # # ]:UBC 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
4921 : :
4922 : : /* Count usage of parameter */
7805 tgl@sss.pgh.pa.us 4923 :CBC 19181 : context->usecounts[param->paramid - 1]++;
4924 : :
4925 : : /* Select the appropriate actual arg and replace the Param with it */
4926 : : /* We don't need to copy at this time (it'll get done later) */
7259 neilc@samurai.com 4927 : 19181 : return list_nth(context->args, param->paramid - 1);
4928 : : }
7805 tgl@sss.pgh.pa.us 4929 : 55678 : return expression_tree_mutator(node, substitute_actual_parameters_mutator,
4930 : : (void *) context);
4931 : : }
4932 : :
4933 : : /*
4934 : : * error context callback to let us supply a call-stack traceback
4935 : : */
4936 : : static void
7566 4937 : 13 : sql_inline_error_callback(void *arg)
4938 : : {
5140 4939 : 13 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
4940 : : int syntaxerrposition;
4941 : :
4942 : : /* If it's a syntax error, convert to internal syntax error report */
1095 4943 : 13 : syntaxerrposition = geterrposition();
4944 [ + + ]: 13 : if (syntaxerrposition > 0)
4945 : : {
4946 : 3 : errposition(0);
4947 : 3 : internalerrposition(syntaxerrposition);
4948 : 3 : internalerrquery(callback_arg->prosrc);
4949 : : }
4950 : :
5140 4951 : 13 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
7566 4952 : 13 : }
4953 : :
4954 : : /*
4955 : : * evaluate_expr: pre-evaluate a constant expression
4956 : : *
4957 : : * We use the executor's routine ExecEvalExpr() to avoid duplication of
4958 : : * code and ensure we get the same result as the executor would get.
4959 : : */
4960 : : Expr *
4769 4961 : 102215 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
4962 : : Oid result_collation)
4963 : : {
4964 : : EState *estate;
4965 : : ExprState *exprstate;
4966 : : MemoryContext oldcontext;
4967 : : Datum const_val;
4968 : : bool const_is_null;
4969 : : int16 resultTypLen;
4970 : : bool resultTypByVal;
4971 : :
4972 : : /*
4973 : : * To use the executor, we need an EState.
4974 : : */
7677 4975 : 102215 : estate = CreateExecutorState();
4976 : :
4977 : : /* We can use the estate's working context to avoid memory leaks. */
4978 : 102215 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
4979 : :
4980 : : /* Make sure any opfuncids are filled in. */
5574 4981 : 102215 : fix_opfuncids((Node *) expr);
4982 : :
4983 : : /*
4984 : : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
4985 : : * because it'd result in recursively invoking eval_const_expressions.)
4986 : : */
4987 : 102215 : exprstate = ExecInitExpr(expr, NULL);
4988 : :
4989 : : /*
4990 : : * And evaluate it.
4991 : : *
4992 : : * It is OK to use a default econtext because none of the ExecEvalExpr()
4993 : : * code used in this situation will use econtext. That might seem
4994 : : * fortuitous, but it's not so unreasonable --- a constant expression does
4995 : : * not depend on context, by definition, n'est ce pas?
4996 : : */
7677 tgl@sss.pgh.pa.us 4997 :UBC 0 : const_val = ExecEvalExprSwitchContext(exprstate,
7677 tgl@sss.pgh.pa.us 4998 [ - + ]:CBC 102206 : GetPerTupleExprContext(estate),
4999 : : &const_is_null);
5000 : :
5001 : : /* Get info needed about result datatype */
5002 : 100406 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5003 : :
5004 : : /* Get back to outer memory context */
5005 : 100406 : MemoryContextSwitchTo(oldcontext);
5006 : :
5007 : : /*
5008 : : * Must copy result out of sub-context used by expression eval.
5009 : : *
5010 : : * Also, if it's varlena, forcibly detoast it. This protects us against
5011 : : * storing TOAST pointers into plans that might outlive the referenced
5012 : : * data. (makeConst would handle detoasting anyway, but it's worth a few
5013 : : * extra lines here so that we can do the copy and detoast in one step.)
5014 : : */
5015 [ + + ]: 100406 : if (!const_is_null)
5016 : : {
6030 5017 [ + + ]: 99709 : if (resultTypLen == -1)
5018 : 38035 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5019 : : else
5020 : 61674 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5021 : : }
5022 : :
5023 : : /* Release all the junk we just created */
7677 5024 : 100406 : FreeExecutorState(estate);
5025 : :
5026 : : /*
5027 : : * Make the constant result node.
5028 : : */
4769 5029 : 100406 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5030 : : resultTypLen,
5031 : : const_val, const_is_null,
5032 : : resultTypByVal);
5033 : : }
5034 : :
5035 : :
5036 : : /*
5037 : : * inline_set_returning_function
5038 : : * Attempt to "inline" a set-returning function in the FROM clause.
5039 : : *
5040 : : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5041 : : * set-returning SQL function that can safely be inlined, expand the function
5042 : : * and return the substitute Query structure. Otherwise, return NULL.
5043 : : *
5044 : : * We assume that the RTE's expression has already been put through
5045 : : * eval_const_expressions(), which among other things will take care of
5046 : : * default arguments and named-argument notation.
5047 : : *
5048 : : * This has a good deal of similarity to inline_function(), but that's
5049 : : * for the non-set-returning case, and there are enough differences to
5050 : : * justify separate functions.
5051 : : */
5052 : : Query *
5666 5053 : 21768 : inline_set_returning_function(PlannerInfo *root, RangeTblEntry *rte)
5054 : : {
5055 : : RangeTblFunction *rtfunc;
5056 : : FuncExpr *fexpr;
5057 : : Oid func_oid;
5058 : : HeapTuple func_tuple;
5059 : : Form_pg_proc funcform;
5060 : : char *src;
5061 : : Datum tmp;
5062 : : bool isNull;
5063 : : MemoryContext oldcxt;
5064 : : MemoryContext mycxt;
5065 : : inline_error_callback_arg callback_arg;
5066 : : ErrorContextCallback sqlerrcontext;
5067 : : SQLFunctionParseInfoPtr pinfo;
5068 : : TypeFuncClass functypclass;
5069 : : TupleDesc rettupdesc;
5070 : : List *raw_parsetree_list;
5071 : : List *querytree_list;
5072 : : Query *querytree;
5073 : :
5074 [ - + ]: 21768 : Assert(rte->rtekind == RTE_FUNCTION);
5075 : :
5076 : : /*
5077 : : * It doesn't make a lot of sense for a SQL SRF to refer to itself in its
5078 : : * own FROM clause, since that must cause infinite recursion at runtime.
5079 : : * It will cause this code to recurse too, so check for stack overflow.
5080 : : * (There's no need to do more.)
5081 : : */
5871 5082 : 21768 : check_stack_depth();
5083 : :
5084 : : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
3912 stark@mit.edu 5085 [ + + ]: 21768 : if (rte->funcordinality)
5086 : 342 : return NULL;
5087 : :
5088 : : /* Fail if RTE isn't a single, simple FuncExpr */
3797 tgl@sss.pgh.pa.us 5089 [ + + ]: 21426 : if (list_length(rte->functions) != 1)
5871 5090 : 36 : return NULL;
3797 5091 : 21390 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5092 : :
5093 [ + + ]: 21390 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5094 : 204 : return NULL;
5095 : 21186 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5096 : :
5302 5097 : 21186 : func_oid = fexpr->funcid;
5098 : :
5099 : : /*
5100 : : * The function must be declared to return a set, else inlining would
5101 : : * change the results if the contained SELECT didn't return exactly one
5102 : : * row.
5103 : : */
5871 5104 [ + + ]: 21186 : if (!fexpr->funcretset)
5105 : 2095 : return NULL;
5106 : :
5107 : : /*
5108 : : * Refuse to inline if the arguments contain any volatile functions or
5109 : : * sub-selects. Volatile functions are rejected because inlining may
5110 : : * result in the arguments being evaluated multiple times, risking a
5111 : : * change in behavior. Sub-selects are rejected partly for implementation
5112 : : * reasons (pushing them down another level might change their behavior)
5113 : : * and partly because they're likely to be expensive and so multiple
5114 : : * evaluation would be bad.
5115 : : */
5116 [ + + + + ]: 38113 : if (contain_volatile_functions((Node *) fexpr->args) ||
5117 : 19022 : contain_subplans((Node *) fexpr->args))
5118 : 191 : return NULL;
5119 : :
5120 : : /* Check permission to call function (fail later, if not) */
518 peter@eisentraut.org 5121 [ + + ]: 18900 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5871 tgl@sss.pgh.pa.us 5122 : 4 : return NULL;
5123 : :
5124 : : /* Check whether a plugin wants to hook function entry/exit */
4871 rhaas@postgresql.org 5125 [ - + - - ]: 18896 : if (FmgrHookIsNeeded(func_oid))
4871 rhaas@postgresql.org 5126 :UBC 0 : return NULL;
5127 : :
5128 : : /*
5129 : : * OK, let's take a look at the function's pg_proc entry.
5130 : : */
5173 rhaas@postgresql.org 5131 :CBC 18896 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5871 tgl@sss.pgh.pa.us 5132 [ - + ]: 18896 : if (!HeapTupleIsValid(func_tuple))
5302 tgl@sss.pgh.pa.us 5133 [ # # ]:UBC 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5871 tgl@sss.pgh.pa.us 5134 :CBC 18896 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5135 : :
5136 : : /*
5137 : : * Forget it if the function is not SQL-language or has other showstopper
5138 : : * properties. In particular it mustn't be declared STRICT, since we
5139 : : * couldn't enforce that. It also mustn't be VOLATILE, because that is
5140 : : * supposed to cause it to be executed with its own snapshot, rather than
5141 : : * sharing the snapshot of the calling query. We also disallow returning
5142 : : * SETOF VOID, because inlining would result in exposing the actual result
5143 : : * of the function's last SELECT, which should not happen in that case.
5144 : : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
5145 : : */
5146 [ + + ]: 18896 : if (funcform->prolang != SQLlanguageId ||
2221 5147 [ + - ]: 288 : funcform->prokind != PROKIND_FUNCTION ||
5871 5148 [ + + ]: 288 : funcform->proisstrict ||
5149 [ + + ]: 258 : funcform->provolatile == PROVOLATILE_VOLATILE ||
2221 5150 [ + + ]: 81 : funcform->prorettype == VOIDOID ||
5871 5151 [ + - ]: 78 : funcform->prosecdef ||
5152 [ + - ]: 78 : !funcform->proretset ||
1718 5153 [ + - ]: 78 : list_length(fexpr->args) != funcform->pronargs ||
2209 andrew@dunslane.net 5154 [ - + ]: 78 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5155 : : {
5871 tgl@sss.pgh.pa.us 5156 : 18818 : ReleaseSysCache(func_tuple);
5157 : 18818 : return NULL;
5158 : : }
5159 : :
5160 : : /*
5161 : : * Make a temporary memory context, so that we don't leak all the stuff
5162 : : * that parsing might create.
5163 : : */
5164 : 78 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5165 : : "inline_set_returning_function",
5166 : : ALLOCSET_DEFAULT_SIZES);
5167 : 78 : oldcxt = MemoryContextSwitchTo(mycxt);
5168 : :
5169 : : /* Fetch the function body */
386 dgustafsson@postgres 5170 : 78 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
1095 tgl@sss.pgh.pa.us 5171 : 78 : src = TextDatumGetCString(tmp);
5172 : :
5173 : : /*
5174 : : * Setup error traceback support for ereport(). This is so that we can
5175 : : * finger the function that bad information came from.
5176 : : */
5140 5177 : 78 : callback_arg.proname = NameStr(funcform->proname);
1095 5178 : 78 : callback_arg.prosrc = src;
5179 : :
5140 5180 : 78 : sqlerrcontext.callback = sql_inline_error_callback;
5181 : 78 : sqlerrcontext.arg = (void *) &callback_arg;
5182 : 78 : sqlerrcontext.previous = error_context_stack;
5183 : 78 : error_context_stack = &sqlerrcontext;
5184 : :
5185 : : /* If we have prosqlbody, pay attention to that not prosrc */
1103 peter@eisentraut.org 5186 : 78 : tmp = SysCacheGetAttr(PROCOID,
5187 : : func_tuple,
5188 : : Anum_pg_proc_prosqlbody,
5189 : : &isNull);
1095 tgl@sss.pgh.pa.us 5190 [ + + ]: 78 : if (!isNull)
5191 : : {
5192 : : Node *n;
5193 : :
1103 peter@eisentraut.org 5194 : 6 : n = stringToNode(TextDatumGetCString(tmp));
5195 [ + - ]: 6 : if (IsA(n, List))
5196 : 6 : querytree_list = linitial_node(List, castNode(List, n));
5197 : : else
1103 peter@eisentraut.org 5198 :UBC 0 : querytree_list = list_make1(n);
1103 peter@eisentraut.org 5199 [ - + ]:CBC 6 : if (list_length(querytree_list) != 1)
1103 peter@eisentraut.org 5200 :UBC 0 : goto fail;
1103 peter@eisentraut.org 5201 :CBC 6 : querytree = linitial(querytree_list);
5202 : :
5203 : : /* Acquire necessary locks, then apply rewriter. */
957 tgl@sss.pgh.pa.us 5204 : 6 : AcquireRewriteLocks(querytree, true, false);
1103 peter@eisentraut.org 5205 : 6 : querytree_list = pg_rewrite_query(querytree);
5206 [ - + ]: 6 : if (list_length(querytree_list) != 1)
1103 peter@eisentraut.org 5207 :UBC 0 : goto fail;
1103 peter@eisentraut.org 5208 :CBC 6 : querytree = linitial(querytree_list);
5209 : : }
5210 : : else
5211 : : {
5212 : : /*
5213 : : * Set up to handle parameters while parsing the function body. We
5214 : : * can use the FuncExpr just created as the input for
5215 : : * prepare_sql_fn_parse_info.
5216 : : */
1068 tgl@sss.pgh.pa.us 5217 : 72 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5218 : : (Node *) fexpr,
5219 : : fexpr->inputcollid);
5220 : :
5221 : : /*
5222 : : * Parse, analyze, and rewrite (unlike inline_function(), we can't
5223 : : * skip rewriting here). We can fail as soon as we find more than one
5224 : : * query, though.
5225 : : */
5226 : 72 : raw_parsetree_list = pg_parse_query(src);
5227 [ - + ]: 72 : if (list_length(raw_parsetree_list) != 1)
1068 tgl@sss.pgh.pa.us 5228 :UBC 0 : goto fail;
5229 : :
772 peter@eisentraut.org 5230 :CBC 72 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
5231 : : src,
5232 : : (ParserSetupHook) sql_fn_parser_setup,
5233 : : pinfo, NULL);
1068 tgl@sss.pgh.pa.us 5234 [ - + ]: 72 : if (list_length(querytree_list) != 1)
1068 tgl@sss.pgh.pa.us 5235 :UBC 0 : goto fail;
1068 tgl@sss.pgh.pa.us 5236 :CBC 72 : querytree = linitial(querytree_list);
5237 : : }
5238 : :
5239 : : /*
5240 : : * Also resolve the actual function result tupdesc, if composite. If we
5241 : : * have a coldeflist, believe that; otherwise use get_expr_result_type.
5242 : : * (This logic should match ExecInitFunctionScan.)
5243 : : */
39 5244 [ + + ]: 78 : if (rtfunc->funccolnames != NIL)
5245 : : {
5246 : 12 : functypclass = TYPEFUNC_RECORD;
1103 peter@eisentraut.org 5247 : 12 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
1103 peter@eisentraut.org 5248 :GIC 12 : rtfunc->funccoltypes,
5249 : 12 : rtfunc->funccoltypmods,
5250 : 12 : rtfunc->funccolcollations);
5251 : : }
5252 : : else
39 tgl@sss.pgh.pa.us 5253 :CBC 66 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
5254 : :
5255 : : /*
5256 : : * The single command must be a plain SELECT.
5257 : : */
5871 5258 [ + - ]: 78 : if (!IsA(querytree, Query) ||
2647 5259 [ - + ]: 78 : querytree->commandType != CMD_SELECT)
5871 tgl@sss.pgh.pa.us 5260 :UBC 0 : goto fail;
5261 : :
5262 : : /*
5263 : : * Make sure the function (still) returns what it's declared to. This
5264 : : * will raise an error if wrong, but that's okay since the function would
5265 : : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5266 : : * coercions if needed to make the tlist expression(s) match the declared
5267 : : * type of the function. We also ask it to insert dummy NULL columns for
5268 : : * any dropped columns in rettupdesc, so that the elements of the modified
5269 : : * tlist match up to the attribute numbers.
5270 : : *
5271 : : * If the function returns a composite type, don't inline unless the check
5272 : : * shows it's returning a whole tuple result; otherwise what it's
5273 : : * returning is a single composite column which is not what we need.
5274 : : */
1273 tgl@sss.pgh.pa.us 5275 [ + + ]:GNC 78 : if (!check_sql_fn_retval(list_make1(querytree_list),
5276 : : fexpr->funcresulttype, rettupdesc,
33 5277 : 78 : funcform->prokind,
1558 5278 [ + - ]: 45 : true, NULL) &&
1558 tgl@sss.pgh.pa.us 5279 [ + - ]:CBC 45 : (functypclass == TYPEFUNC_COMPOSITE ||
5280 [ - + ]: 45 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
5281 : : functypclass == TYPEFUNC_RECORD))
5871 tgl@sss.pgh.pa.us 5282 :UBC 0 : goto fail; /* reject not-whole-tuple-result cases */
5283 : :
5284 : : /*
5285 : : * check_sql_fn_retval might've inserted a projection step, but that's
5286 : : * fine; just make sure we use the upper Query.
5287 : : */
1273 tgl@sss.pgh.pa.us 5288 :CBC 75 : querytree = linitial_node(Query, querytree_list);
5289 : :
5290 : : /*
5291 : : * Looks good --- substitute parameters into the query.
5292 : : */
5871 5293 : 75 : querytree = substitute_actual_srf_parameters(querytree,
5294 : 75 : funcform->pronargs,
5295 : : fexpr->args);
5296 : :
5297 : : /*
5298 : : * Copy the modified query out of the temporary memory context, and clean
5299 : : * up.
5300 : : */
5301 : 75 : MemoryContextSwitchTo(oldcxt);
5302 : :
5303 : 75 : querytree = copyObject(querytree);
5304 : :
5305 : 75 : MemoryContextDelete(mycxt);
5306 : 75 : error_context_stack = sqlerrcontext.previous;
5307 : 75 : ReleaseSysCache(func_tuple);
5308 : :
5309 : : /*
5310 : : * We don't have to fix collations here because the upper query is already
5311 : : * parsed, ie, the collations in the RTE are what count.
5312 : : */
5313 : :
5314 : : /*
5315 : : * Since there is now no trace of the function in the plan tree, we must
5316 : : * explicitly record the plan's dependency on the function.
5317 : : */
4607 5318 : 75 : record_plan_function_dependency(root, func_oid);
5319 : :
5320 : : /*
5321 : : * We must also notice if the inserted query adds a dependency on the
5322 : : * calling role due to RLS quals.
5323 : : */
342 5324 [ + + ]: 75 : if (querytree->hasRowSecurity)
5325 : 6 : root->glob->dependsOnRole = true;
5326 : :
5871 5327 : 75 : return querytree;
5328 : :
5329 : : /* Here if func is not inlinable: release temp memory and return NULL */
5871 tgl@sss.pgh.pa.us 5330 :UBC 0 : fail:
5331 : 0 : MemoryContextSwitchTo(oldcxt);
5332 : 0 : MemoryContextDelete(mycxt);
5333 : 0 : error_context_stack = sqlerrcontext.previous;
5334 : 0 : ReleaseSysCache(func_tuple);
5335 : :
5336 : 0 : return NULL;
5337 : : }
5338 : :
5339 : : /*
5340 : : * Replace Param nodes by appropriate actual parameters
5341 : : *
5342 : : * This is just enough different from substitute_actual_parameters()
5343 : : * that it needs its own code.
5344 : : */
5345 : : static Query *
5871 tgl@sss.pgh.pa.us 5346 :CBC 75 : substitute_actual_srf_parameters(Query *expr, int nargs, List *args)
5347 : : {
5348 : : substitute_actual_srf_parameters_context context;
5349 : :
5350 : 75 : context.nargs = nargs;
5351 : 75 : context.args = args;
5352 : 75 : context.sublevels_up = 1;
5353 : :
5354 : 75 : return query_tree_mutator(expr,
5355 : : substitute_actual_srf_parameters_mutator,
5356 : : &context,
5357 : : 0);
5358 : : }
5359 : :
5360 : : static Node *
5361 : 2643 : substitute_actual_srf_parameters_mutator(Node *node,
5362 : : substitute_actual_srf_parameters_context *context)
5363 : : {
5364 : : Node *result;
5365 : :
5366 [ + + ]: 2643 : if (node == NULL)
5367 : 1440 : return NULL;
5368 [ + + ]: 1203 : if (IsA(node, Query))
5369 : : {
5370 : 39 : context->sublevels_up++;
5371 : 39 : result = (Node *) query_tree_mutator((Query *) node,
5372 : : substitute_actual_srf_parameters_mutator,
5373 : : (void *) context,
5374 : : 0);
5375 : 39 : context->sublevels_up--;
5376 : 39 : return result;
5377 : : }
5378 [ + + ]: 1164 : if (IsA(node, Param))
5379 : : {
5380 : 51 : Param *param = (Param *) node;
5381 : :
5382 [ + - ]: 51 : if (param->paramkind == PARAM_EXTERN)
5383 : : {
5384 [ + - - + ]: 51 : if (param->paramid <= 0 || param->paramid > context->nargs)
5871 tgl@sss.pgh.pa.us 5385 [ # # ]:UBC 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5386 : :
5387 : : /*
5388 : : * Since the parameter is being inserted into a subquery, we must
5389 : : * adjust levels.
5390 : : */
5871 tgl@sss.pgh.pa.us 5391 :CBC 51 : result = copyObject(list_nth(context->args, param->paramid - 1));
5392 : 51 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
5393 : 51 : return result;
5394 : : }
5395 : : }
5396 : 1113 : return expression_tree_mutator(node,
5397 : : substitute_actual_srf_parameters_mutator,
5398 : : (void *) context);
5399 : : }
5400 : :
5401 : : /*
5402 : : * pull_paramids
5403 : : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
5404 : : */
5405 : : Bitmapset *
872 drowley@postgresql.o 5406 : 670 : pull_paramids(Expr *expr)
5407 : : {
5408 : 670 : Bitmapset *result = NULL;
5409 : :
5410 : 670 : (void) pull_paramids_walker((Node *) expr, &result);
5411 : :
5412 : 670 : return result;
5413 : : }
5414 : :
5415 : : static bool
5416 : 1476 : pull_paramids_walker(Node *node, Bitmapset **context)
5417 : : {
5418 [ + + ]: 1476 : if (node == NULL)
5419 : 15 : return false;
5420 [ + + ]: 1461 : if (IsA(node, Param))
5421 : : {
703 tgl@sss.pgh.pa.us 5422 : 685 : Param *param = (Param *) node;
5423 : :
872 drowley@postgresql.o 5424 : 685 : *context = bms_add_member(*context, param->paramid);
5425 : 685 : return false;
5426 : : }
5427 : 776 : return expression_tree_walker(node, pull_paramids_walker,
5428 : : (void *) context);
5429 : : }
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