Line data Source code
1 : /*-------------------------------------------------------------------------
2 : *
3 : * clauses.c
4 : * routines to manipulate qualification clauses
5 : *
6 : * Portions Copyright (c) 1996-2026, 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_class.h"
24 : #include "catalog/pg_language.h"
25 : #include "catalog/pg_operator.h"
26 : #include "catalog/pg_proc.h"
27 : #include "catalog/pg_type.h"
28 : #include "executor/executor.h"
29 : #include "executor/functions.h"
30 : #include "funcapi.h"
31 : #include "miscadmin.h"
32 : #include "nodes/makefuncs.h"
33 : #include "nodes/multibitmapset.h"
34 : #include "nodes/nodeFuncs.h"
35 : #include "nodes/subscripting.h"
36 : #include "nodes/supportnodes.h"
37 : #include "optimizer/clauses.h"
38 : #include "optimizer/cost.h"
39 : #include "optimizer/optimizer.h"
40 : #include "optimizer/pathnode.h"
41 : #include "optimizer/plancat.h"
42 : #include "optimizer/planmain.h"
43 : #include "parser/analyze.h"
44 : #include "parser/parse_coerce.h"
45 : #include "parser/parse_collate.h"
46 : #include "parser/parse_func.h"
47 : #include "parser/parse_oper.h"
48 : #include "parser/parsetree.h"
49 : #include "rewrite/rewriteHandler.h"
50 : #include "rewrite/rewriteManip.h"
51 : #include "tcop/tcopprot.h"
52 : #include "utils/acl.h"
53 : #include "utils/builtins.h"
54 : #include "utils/datum.h"
55 : #include "utils/fmgroids.h"
56 : #include "utils/json.h"
57 : #include "utils/jsonb.h"
58 : #include "utils/jsonpath.h"
59 : #include "utils/lsyscache.h"
60 : #include "utils/memutils.h"
61 : #include "utils/syscache.h"
62 : #include "utils/typcache.h"
63 :
64 : typedef struct
65 : {
66 : ParamListInfo boundParams;
67 : PlannerInfo *root;
68 : List *active_fns;
69 : Node *case_val;
70 : bool estimate;
71 : } eval_const_expressions_context;
72 :
73 : typedef struct
74 : {
75 : int nargs;
76 : List *args;
77 : int *usecounts;
78 : } substitute_actual_parameters_context;
79 :
80 : typedef struct
81 : {
82 : int nargs;
83 : List *args;
84 : int sublevels_up;
85 : } substitute_actual_parameters_in_from_context;
86 :
87 : typedef struct
88 : {
89 : char *proname;
90 : char *prosrc;
91 : } inline_error_callback_arg;
92 :
93 : typedef struct
94 : {
95 : char max_hazard; /* worst proparallel hazard found so far */
96 : char max_interesting; /* worst proparallel hazard of interest */
97 : List *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
98 : } max_parallel_hazard_context;
99 :
100 : static bool contain_agg_clause_walker(Node *node, void *context);
101 : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
102 : static bool contain_subplans_walker(Node *node, void *context);
103 : static bool contain_mutable_functions_walker(Node *node, void *context);
104 : static bool contain_volatile_functions_walker(Node *node, void *context);
105 : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
106 : static bool max_parallel_hazard_walker(Node *node,
107 : max_parallel_hazard_context *context);
108 : static bool contain_nonstrict_functions_walker(Node *node, void *context);
109 : static bool contain_exec_param_walker(Node *node, List *param_ids);
110 : static bool contain_context_dependent_node(Node *clause);
111 : static bool contain_context_dependent_node_walker(Node *node, int *flags);
112 : static bool contain_leaked_vars_walker(Node *node, void *context);
113 : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
114 : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
115 : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
116 : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
117 : static Node *eval_const_expressions_mutator(Node *node,
118 : eval_const_expressions_context *context);
119 : static bool contain_non_const_walker(Node *node, void *context);
120 : static bool ece_function_is_safe(Oid funcid,
121 : eval_const_expressions_context *context);
122 : static List *simplify_or_arguments(List *args,
123 : eval_const_expressions_context *context,
124 : bool *haveNull, bool *forceTrue);
125 : static List *simplify_and_arguments(List *args,
126 : eval_const_expressions_context *context,
127 : bool *haveNull, bool *forceFalse);
128 : static Node *simplify_boolean_equality(Oid opno, List *args);
129 : static Expr *simplify_function(Oid funcid,
130 : Oid result_type, int32 result_typmod,
131 : Oid result_collid, Oid input_collid, List **args_p,
132 : bool funcvariadic, bool process_args, bool allow_non_const,
133 : eval_const_expressions_context *context);
134 : static Node *simplify_aggref(Aggref *aggref,
135 : eval_const_expressions_context *context);
136 : static List *reorder_function_arguments(List *args, int pronargs,
137 : HeapTuple func_tuple);
138 : static List *add_function_defaults(List *args, int pronargs,
139 : HeapTuple func_tuple);
140 : static List *fetch_function_defaults(HeapTuple func_tuple);
141 : static void recheck_cast_function_args(List *args, Oid result_type,
142 : Oid *proargtypes, int pronargs,
143 : HeapTuple func_tuple);
144 : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
145 : Oid result_collid, Oid input_collid, List *args,
146 : bool funcvariadic,
147 : HeapTuple func_tuple,
148 : eval_const_expressions_context *context);
149 : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
150 : Oid input_collid, List *args,
151 : bool funcvariadic,
152 : HeapTuple func_tuple,
153 : eval_const_expressions_context *context);
154 : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
155 : int *usecounts);
156 : static Node *substitute_actual_parameters_mutator(Node *node,
157 : substitute_actual_parameters_context *context);
158 : static void sql_inline_error_callback(void *arg);
159 : static Query *inline_sql_function_in_from(PlannerInfo *root,
160 : RangeTblFunction *rtfunc,
161 : FuncExpr *fexpr,
162 : HeapTuple func_tuple,
163 : Form_pg_proc funcform,
164 : const char *src);
165 : static Query *substitute_actual_parameters_in_from(Query *expr,
166 : int nargs, List *args);
167 : static Node *substitute_actual_parameters_in_from_mutator(Node *node,
168 : substitute_actual_parameters_in_from_context *context);
169 : static bool pull_paramids_walker(Node *node, Bitmapset **context);
170 :
171 :
172 : /*****************************************************************************
173 : * Aggregate-function clause manipulation
174 : *****************************************************************************/
175 :
176 : /*
177 : * contain_agg_clause
178 : * Recursively search for Aggref/GroupingFunc nodes within a clause.
179 : *
180 : * Returns true if any aggregate found.
181 : *
182 : * This does not descend into subqueries, and so should be used only after
183 : * reduction of sublinks to subplans, or in contexts where it's known there
184 : * are no subqueries. There mustn't be outer-aggregate references either.
185 : *
186 : * (If you want something like this but able to deal with subqueries,
187 : * see rewriteManip.c's contain_aggs_of_level().)
188 : */
189 : bool
190 10886 : contain_agg_clause(Node *clause)
191 : {
192 10886 : return contain_agg_clause_walker(clause, NULL);
193 : }
194 :
195 : static bool
196 13172 : contain_agg_clause_walker(Node *node, void *context)
197 : {
198 13172 : if (node == NULL)
199 36 : return false;
200 13136 : if (IsA(node, Aggref))
201 : {
202 : Assert(((Aggref *) node)->agglevelsup == 0);
203 1018 : return true; /* abort the tree traversal and return true */
204 : }
205 12118 : if (IsA(node, GroupingFunc))
206 : {
207 : Assert(((GroupingFunc *) node)->agglevelsup == 0);
208 30 : return true; /* abort the tree traversal and return true */
209 : }
210 : Assert(!IsA(node, SubLink));
211 12088 : return expression_tree_walker(node, contain_agg_clause_walker, context);
212 : }
213 :
214 : /*****************************************************************************
215 : * Window-function clause manipulation
216 : *****************************************************************************/
217 :
218 : /*
219 : * contain_window_function
220 : * Recursively search for WindowFunc nodes within a clause.
221 : *
222 : * Since window functions don't have level fields, but are hard-wired to
223 : * be associated with the current query level, this is just the same as
224 : * rewriteManip.c's function.
225 : */
226 : bool
227 9340 : contain_window_function(Node *clause)
228 : {
229 9340 : return contain_windowfuncs(clause);
230 : }
231 :
232 : /*
233 : * find_window_functions
234 : * Locate all the WindowFunc nodes in an expression tree, and organize
235 : * them by winref ID number.
236 : *
237 : * Caller must provide an upper bound on the winref IDs expected in the tree.
238 : */
239 : WindowFuncLists *
240 2582 : find_window_functions(Node *clause, Index maxWinRef)
241 : {
242 2582 : WindowFuncLists *lists = palloc_object(WindowFuncLists);
243 :
244 2582 : lists->numWindowFuncs = 0;
245 2582 : lists->maxWinRef = maxWinRef;
246 2582 : lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
247 2582 : (void) find_window_functions_walker(clause, lists);
248 2582 : return lists;
249 : }
250 :
251 : static bool
252 21958 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
253 : {
254 21958 : if (node == NULL)
255 218 : return false;
256 21740 : if (IsA(node, WindowFunc))
257 : {
258 3608 : WindowFunc *wfunc = (WindowFunc *) node;
259 :
260 : /* winref is unsigned, so one-sided test is OK */
261 3608 : if (wfunc->winref > lists->maxWinRef)
262 0 : elog(ERROR, "WindowFunc contains out-of-range winref %u",
263 : wfunc->winref);
264 : /* eliminate duplicates, so that we avoid repeated computation */
265 3608 : if (!list_member(lists->windowFuncs[wfunc->winref], wfunc))
266 : {
267 7192 : lists->windowFuncs[wfunc->winref] =
268 3596 : lappend(lists->windowFuncs[wfunc->winref], wfunc);
269 3596 : lists->numWindowFuncs++;
270 : }
271 :
272 : /*
273 : * We assume that the parser checked that there are no window
274 : * functions in the arguments or filter clause. Hence, we need not
275 : * recurse into them. (If either the parser or the planner screws up
276 : * on this point, the executor will still catch it; see ExecInitExpr.)
277 : */
278 3608 : return false;
279 : }
280 : Assert(!IsA(node, SubLink));
281 18132 : return expression_tree_walker(node, find_window_functions_walker, lists);
282 : }
283 :
284 :
285 : /*****************************************************************************
286 : * Support for expressions returning sets
287 : *****************************************************************************/
288 :
289 : /*
290 : * expression_returns_set_rows
291 : * Estimate the number of rows returned by a set-returning expression.
292 : * The result is 1 if it's not a set-returning expression.
293 : *
294 : * We should only examine the top-level function or operator; it used to be
295 : * appropriate to recurse, but not anymore. (Even if there are more SRFs in
296 : * the function's inputs, their multipliers are accounted for separately.)
297 : *
298 : * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
299 : */
300 : double
301 462218 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
302 : {
303 462218 : if (clause == NULL)
304 0 : return 1.0;
305 462218 : if (IsA(clause, FuncExpr))
306 : {
307 66534 : FuncExpr *expr = (FuncExpr *) clause;
308 :
309 66534 : if (expr->funcretset)
310 56706 : return clamp_row_est(get_function_rows(root, expr->funcid, clause));
311 : }
312 405512 : if (IsA(clause, OpExpr))
313 : {
314 3810 : OpExpr *expr = (OpExpr *) clause;
315 :
316 3810 : if (expr->opretset)
317 : {
318 6 : set_opfuncid(expr);
319 6 : return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
320 : }
321 : }
322 405506 : return 1.0;
323 : }
324 :
325 :
326 : /*****************************************************************************
327 : * Subplan clause manipulation
328 : *****************************************************************************/
329 :
330 : /*
331 : * contain_subplans
332 : * Recursively search for subplan nodes within a clause.
333 : *
334 : * If we see a SubLink node, we will return true. This is only possible if
335 : * the expression tree hasn't yet been transformed by subselect.c. We do not
336 : * know whether the node will produce a true subplan or just an initplan,
337 : * but we make the conservative assumption that it will be a subplan.
338 : *
339 : * Returns true if any subplan found.
340 : */
341 : bool
342 58660 : contain_subplans(Node *clause)
343 : {
344 58660 : return contain_subplans_walker(clause, NULL);
345 : }
346 :
347 : static bool
348 256796 : contain_subplans_walker(Node *node, void *context)
349 : {
350 256796 : if (node == NULL)
351 7912 : return false;
352 248884 : if (IsA(node, SubPlan) ||
353 248782 : IsA(node, AlternativeSubPlan) ||
354 248782 : IsA(node, SubLink))
355 344 : return true; /* abort the tree traversal and return true */
356 248540 : return expression_tree_walker(node, contain_subplans_walker, context);
357 : }
358 :
359 :
360 : /*****************************************************************************
361 : * Check clauses for mutable functions
362 : *****************************************************************************/
363 :
364 : /*
365 : * contain_mutable_functions
366 : * Recursively search for mutable functions within a clause.
367 : *
368 : * Returns true if any mutable function (or operator implemented by a
369 : * mutable function) is found. This test is needed so that we don't
370 : * mistakenly think that something like "WHERE random() < 0.5" can be treated
371 : * as a constant qualification.
372 : *
373 : * This will give the right answer only for clauses that have been put
374 : * through expression preprocessing. Callers outside the planner typically
375 : * should use contain_mutable_functions_after_planning() instead, for the
376 : * reasons given there.
377 : *
378 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
379 : * but not into SubPlans. See comments for contain_volatile_functions().
380 : */
381 : bool
382 169916 : contain_mutable_functions(Node *clause)
383 : {
384 169916 : return contain_mutable_functions_walker(clause, NULL);
385 : }
386 :
387 : static bool
388 123154 : contain_mutable_functions_checker(Oid func_id, void *context)
389 : {
390 123154 : return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
391 : }
392 :
393 : static bool
394 445360 : contain_mutable_functions_walker(Node *node, void *context)
395 : {
396 445360 : if (node == NULL)
397 2318 : return false;
398 : /* Check for mutable functions in node itself */
399 443042 : if (check_functions_in_node(node, contain_mutable_functions_checker,
400 : context))
401 6994 : return true;
402 :
403 436048 : if (IsA(node, JsonConstructorExpr))
404 : {
405 0 : const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
406 : ListCell *lc;
407 : bool is_jsonb;
408 :
409 0 : is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
410 :
411 : /*
412 : * Check argument_type => json[b] conversions specifically. We still
413 : * recurse to check 'args' below, but here we want to specifically
414 : * check whether or not the emitted clause would fail to be immutable
415 : * because of TimeZone, for example.
416 : */
417 0 : foreach(lc, ctor->args)
418 : {
419 0 : Oid typid = exprType(lfirst(lc));
420 :
421 0 : if (is_jsonb ?
422 0 : !to_jsonb_is_immutable(typid) :
423 0 : !to_json_is_immutable(typid))
424 0 : return true;
425 : }
426 :
427 : /* Check all subnodes */
428 : }
429 :
430 436048 : if (IsA(node, JsonExpr))
431 : {
432 234 : JsonExpr *jexpr = castNode(JsonExpr, node);
433 : Const *cnst;
434 :
435 234 : if (!IsA(jexpr->path_spec, Const))
436 0 : return true;
437 :
438 234 : cnst = castNode(Const, jexpr->path_spec);
439 :
440 : Assert(cnst->consttype == JSONPATHOID);
441 234 : if (cnst->constisnull)
442 0 : return false;
443 :
444 234 : if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
445 : jexpr->passing_names, jexpr->passing_values))
446 162 : return true;
447 : }
448 :
449 435886 : if (IsA(node, SQLValueFunction))
450 : {
451 : /* all variants of SQLValueFunction are stable */
452 430 : return true;
453 : }
454 :
455 435456 : if (IsA(node, NextValueExpr))
456 : {
457 : /* NextValueExpr is volatile */
458 0 : return true;
459 : }
460 :
461 : /*
462 : * It should be safe to treat MinMaxExpr as immutable, because it will
463 : * depend on a non-cross-type btree comparison function, and those should
464 : * always be immutable. Treating XmlExpr as immutable is more dubious,
465 : * and treating CoerceToDomain as immutable is outright dangerous. But we
466 : * have done so historically, and changing this would probably cause more
467 : * problems than it would fix. In practice, if you have a non-immutable
468 : * domain constraint you are in for pain anyhow.
469 : */
470 :
471 : /* Recurse to check arguments */
472 435456 : if (IsA(node, Query))
473 : {
474 : /* Recurse into subselects */
475 0 : return query_tree_walker((Query *) node,
476 : contain_mutable_functions_walker,
477 : context, 0);
478 : }
479 435456 : return expression_tree_walker(node, contain_mutable_functions_walker,
480 : context);
481 : }
482 :
483 : /*
484 : * contain_mutable_functions_after_planning
485 : * Test whether given expression contains mutable functions.
486 : *
487 : * This is a wrapper for contain_mutable_functions() that is safe to use from
488 : * outside the planner. The difference is that it first runs the expression
489 : * through expression_planner(). There are two key reasons why we need that:
490 : *
491 : * First, function default arguments will get inserted, which may affect
492 : * volatility (consider "default now()").
493 : *
494 : * Second, inline-able functions will get inlined, which may allow us to
495 : * conclude that the function is really less volatile than it's marked.
496 : * As an example, polymorphic functions must be marked with the most volatile
497 : * behavior that they have for any input type, but once we inline the
498 : * function we may be able to conclude that it's not so volatile for the
499 : * particular input type we're dealing with.
500 : */
501 : bool
502 3400 : contain_mutable_functions_after_planning(Expr *expr)
503 : {
504 : /* We assume here that expression_planner() won't scribble on its input */
505 3400 : expr = expression_planner(expr);
506 :
507 : /* Now we can search for non-immutable functions */
508 3400 : return contain_mutable_functions((Node *) expr);
509 : }
510 :
511 :
512 : /*****************************************************************************
513 : * Check clauses for volatile functions
514 : *****************************************************************************/
515 :
516 : /*
517 : * contain_volatile_functions
518 : * Recursively search for volatile functions within a clause.
519 : *
520 : * Returns true if any volatile function (or operator implemented by a
521 : * volatile function) is found. This test prevents, for example,
522 : * invalid conversions of volatile expressions into indexscan quals.
523 : *
524 : * This will give the right answer only for clauses that have been put
525 : * through expression preprocessing. Callers outside the planner typically
526 : * should use contain_volatile_functions_after_planning() instead, for the
527 : * reasons given there.
528 : *
529 : * We will recursively look into Query nodes (i.e., SubLink sub-selects)
530 : * but not into SubPlans. This is a bit odd, but intentional. If we are
531 : * looking at a SubLink, we are probably deciding whether a query tree
532 : * transformation is safe, and a contained sub-select should affect that;
533 : * for example, duplicating a sub-select containing a volatile function
534 : * would be bad. However, once we've got to the stage of having SubPlans,
535 : * subsequent planning need not consider volatility within those, since
536 : * the executor won't change its evaluation rules for a SubPlan based on
537 : * volatility.
538 : *
539 : * For some node types, for example, RestrictInfo and PathTarget, we cache
540 : * whether we found any volatile functions or not and reuse that value in any
541 : * future checks for that node. All of the logic for determining if the
542 : * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
543 : * belongs in this function. Any code which makes changes to these nodes
544 : * which could change the outcome this function must set the cached value back
545 : * to VOLATILITY_UNKNOWN. That allows this function to redetermine the
546 : * correct value during the next call, should we need to redetermine if the
547 : * node contains any volatile functions again in the future.
548 : */
549 : bool
550 3487426 : contain_volatile_functions(Node *clause)
551 : {
552 3487426 : return contain_volatile_functions_walker(clause, NULL);
553 : }
554 :
555 : static bool
556 946508 : contain_volatile_functions_checker(Oid func_id, void *context)
557 : {
558 946508 : return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
559 : }
560 :
561 : static bool
562 7969654 : contain_volatile_functions_walker(Node *node, void *context)
563 : {
564 7969654 : if (node == NULL)
565 229704 : return false;
566 : /* Check for volatile functions in node itself */
567 7739950 : if (check_functions_in_node(node, contain_volatile_functions_checker,
568 : context))
569 2048 : return true;
570 :
571 7737902 : if (IsA(node, NextValueExpr))
572 : {
573 : /* NextValueExpr is volatile */
574 42 : return true;
575 : }
576 :
577 7737860 : if (IsA(node, RestrictInfo))
578 : {
579 1360406 : RestrictInfo *rinfo = (RestrictInfo *) node;
580 :
581 : /*
582 : * For RestrictInfo, check if we've checked the volatility of it
583 : * before. If so, we can just use the cached value and not bother
584 : * checking it again. Otherwise, check it and cache if whether we
585 : * found any volatile functions.
586 : */
587 1360406 : if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
588 838960 : return false;
589 521446 : else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
590 80 : return true;
591 : else
592 : {
593 : bool hasvolatile;
594 :
595 521366 : hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
596 : context);
597 521366 : if (hasvolatile)
598 136 : rinfo->has_volatile = VOLATILITY_VOLATILE;
599 : else
600 521230 : rinfo->has_volatile = VOLATILITY_NOVOLATILE;
601 :
602 521366 : return hasvolatile;
603 : }
604 : }
605 :
606 6377454 : if (IsA(node, PathTarget))
607 : {
608 398430 : PathTarget *target = (PathTarget *) node;
609 :
610 : /*
611 : * We also do caching for PathTarget the same as we do above for
612 : * RestrictInfos.
613 : */
614 398430 : if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
615 330088 : return false;
616 68342 : else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
617 0 : return true;
618 : else
619 : {
620 : bool hasvolatile;
621 :
622 68342 : hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
623 : context);
624 :
625 68342 : if (hasvolatile)
626 0 : target->has_volatile_expr = VOLATILITY_VOLATILE;
627 : else
628 68342 : target->has_volatile_expr = VOLATILITY_NOVOLATILE;
629 :
630 68342 : return hasvolatile;
631 : }
632 : }
633 :
634 : /*
635 : * See notes in contain_mutable_functions_walker about why we treat
636 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
637 : * SQLValueFunction is stable. Hence, none of them are of interest here.
638 : */
639 :
640 : /* Recurse to check arguments */
641 5979024 : if (IsA(node, Query))
642 : {
643 : /* Recurse into subselects */
644 7212 : return query_tree_walker((Query *) node,
645 : contain_volatile_functions_walker,
646 : context, 0);
647 : }
648 5971812 : return expression_tree_walker(node, contain_volatile_functions_walker,
649 : context);
650 : }
651 :
652 : /*
653 : * contain_volatile_functions_after_planning
654 : * Test whether given expression contains volatile functions.
655 : *
656 : * This is a wrapper for contain_volatile_functions() that is safe to use from
657 : * outside the planner. The difference is that it first runs the expression
658 : * through expression_planner(). There are two key reasons why we need that:
659 : *
660 : * First, function default arguments will get inserted, which may affect
661 : * volatility (consider "default random()").
662 : *
663 : * Second, inline-able functions will get inlined, which may allow us to
664 : * conclude that the function is really less volatile than it's marked.
665 : * As an example, polymorphic functions must be marked with the most volatile
666 : * behavior that they have for any input type, but once we inline the
667 : * function we may be able to conclude that it's not so volatile for the
668 : * particular input type we're dealing with.
669 : */
670 : bool
671 0 : contain_volatile_functions_after_planning(Expr *expr)
672 : {
673 : /* We assume here that expression_planner() won't scribble on its input */
674 0 : expr = expression_planner(expr);
675 :
676 : /* Now we can search for volatile functions */
677 0 : return contain_volatile_functions((Node *) expr);
678 : }
679 :
680 : /*
681 : * Special purpose version of contain_volatile_functions() for use in COPY:
682 : * ignore nextval(), but treat all other functions normally.
683 : */
684 : bool
685 252 : contain_volatile_functions_not_nextval(Node *clause)
686 : {
687 252 : return contain_volatile_functions_not_nextval_walker(clause, NULL);
688 : }
689 :
690 : static bool
691 64 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
692 : {
693 104 : return (func_id != F_NEXTVAL &&
694 40 : func_volatile(func_id) == PROVOLATILE_VOLATILE);
695 : }
696 :
697 : static bool
698 312 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
699 : {
700 312 : if (node == NULL)
701 0 : return false;
702 : /* Check for volatile functions in node itself */
703 312 : if (check_functions_in_node(node,
704 : contain_volatile_functions_not_nextval_checker,
705 : context))
706 6 : return true;
707 :
708 : /*
709 : * See notes in contain_mutable_functions_walker about why we treat
710 : * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
711 : * SQLValueFunction is stable. Hence, none of them are of interest here.
712 : * Also, since we're intentionally ignoring nextval(), presumably we
713 : * should ignore NextValueExpr.
714 : */
715 :
716 : /* Recurse to check arguments */
717 306 : if (IsA(node, Query))
718 : {
719 : /* Recurse into subselects */
720 0 : return query_tree_walker((Query *) node,
721 : contain_volatile_functions_not_nextval_walker,
722 : context, 0);
723 : }
724 306 : return expression_tree_walker(node,
725 : contain_volatile_functions_not_nextval_walker,
726 : context);
727 : }
728 :
729 :
730 : /*****************************************************************************
731 : * Check queries for parallel unsafe and/or restricted constructs
732 : *****************************************************************************/
733 :
734 : /*
735 : * max_parallel_hazard
736 : * Find the worst parallel-hazard level in the given query
737 : *
738 : * Returns the worst function hazard property (the earliest in this list:
739 : * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
740 : * be found in the given parsetree. We use this to find out whether the query
741 : * can be parallelized at all. The caller will also save the result in
742 : * PlannerGlobal so as to short-circuit checks of portions of the querytree
743 : * later, in the common case where everything is SAFE.
744 : */
745 : char
746 351216 : max_parallel_hazard(Query *parse)
747 : {
748 : max_parallel_hazard_context context;
749 :
750 351216 : context.max_hazard = PROPARALLEL_SAFE;
751 351216 : context.max_interesting = PROPARALLEL_UNSAFE;
752 351216 : context.safe_param_ids = NIL;
753 351216 : (void) max_parallel_hazard_walker((Node *) parse, &context);
754 351216 : return context.max_hazard;
755 : }
756 :
757 : /*
758 : * is_parallel_safe
759 : * Detect whether the given expr contains only parallel-safe functions
760 : *
761 : * root->glob->maxParallelHazard must previously have been set to the
762 : * result of max_parallel_hazard() on the whole query.
763 : */
764 : bool
765 2452210 : is_parallel_safe(PlannerInfo *root, Node *node)
766 : {
767 : max_parallel_hazard_context context;
768 : PlannerInfo *proot;
769 : ListCell *l;
770 :
771 : /*
772 : * Even if the original querytree contained nothing unsafe, we need to
773 : * search the expression if we have generated any PARAM_EXEC Params while
774 : * planning, because those are parallel-restricted and there might be one
775 : * in this expression. But otherwise we don't need to look.
776 : */
777 2452210 : if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
778 1464380 : root->glob->paramExecTypes == NIL)
779 1431616 : return true;
780 : /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
781 1020594 : context.max_hazard = PROPARALLEL_SAFE;
782 1020594 : context.max_interesting = PROPARALLEL_RESTRICTED;
783 1020594 : context.safe_param_ids = NIL;
784 :
785 : /*
786 : * The params that refer to the same or parent query level are considered
787 : * parallel-safe. The idea is that we compute such params at Gather or
788 : * Gather Merge node and pass their value to workers.
789 : */
790 2446808 : for (proot = root; proot != NULL; proot = proot->parent_root)
791 : {
792 1503474 : foreach(l, proot->init_plans)
793 : {
794 77260 : SubPlan *initsubplan = (SubPlan *) lfirst(l);
795 :
796 77260 : context.safe_param_ids = list_concat(context.safe_param_ids,
797 77260 : initsubplan->setParam);
798 : }
799 : }
800 :
801 1020594 : return !max_parallel_hazard_walker(node, &context);
802 : }
803 :
804 : /* core logic for all parallel-hazard checks */
805 : static bool
806 1641982 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
807 : {
808 1641982 : switch (proparallel)
809 : {
810 1352150 : case PROPARALLEL_SAFE:
811 : /* nothing to see here, move along */
812 1352150 : break;
813 210808 : case PROPARALLEL_RESTRICTED:
814 : /* increase max_hazard to RESTRICTED */
815 : Assert(context->max_hazard != PROPARALLEL_UNSAFE);
816 210808 : context->max_hazard = proparallel;
817 : /* done if we are not expecting any unsafe functions */
818 210808 : if (context->max_interesting == proparallel)
819 106906 : return true;
820 103902 : break;
821 79024 : case PROPARALLEL_UNSAFE:
822 79024 : context->max_hazard = proparallel;
823 : /* we're always done at the first unsafe construct */
824 79024 : return true;
825 0 : default:
826 0 : elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
827 : break;
828 : }
829 1456052 : return false;
830 : }
831 :
832 : /* check_functions_in_node callback */
833 : static bool
834 1501430 : max_parallel_hazard_checker(Oid func_id, void *context)
835 : {
836 1501430 : return max_parallel_hazard_test(func_parallel(func_id),
837 : (max_parallel_hazard_context *) context);
838 : }
839 :
840 : static bool
841 21359908 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
842 : {
843 21359908 : if (node == NULL)
844 5735776 : return false;
845 :
846 : /* Check for hazardous functions in node itself */
847 15624132 : if (check_functions_in_node(node, max_parallel_hazard_checker,
848 : context))
849 108000 : return true;
850 :
851 : /*
852 : * It should be OK to treat MinMaxExpr as parallel-safe, since btree
853 : * opclass support functions are generally parallel-safe. XmlExpr is a
854 : * bit more dubious but we can probably get away with it. We err on the
855 : * side of caution by treating CoerceToDomain as parallel-restricted.
856 : * (Note: in principle that's wrong because a domain constraint could
857 : * contain a parallel-unsafe function; but useful constraints probably
858 : * never would have such, and assuming they do would cripple use of
859 : * parallel query in the presence of domain types.) SQLValueFunction
860 : * should be safe in all cases. NextValueExpr is parallel-unsafe.
861 : */
862 15516132 : if (IsA(node, CoerceToDomain))
863 : {
864 19648 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
865 6404 : return true;
866 : }
867 :
868 15496484 : else if (IsA(node, NextValueExpr))
869 : {
870 386 : if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
871 386 : return true;
872 : }
873 :
874 : /*
875 : * Treat window functions as parallel-restricted because we aren't sure
876 : * whether the input row ordering is fully deterministic, and the output
877 : * of window functions might vary across workers if not. (In some cases,
878 : * like where the window frame orders by a primary key, we could relax
879 : * this restriction. But it doesn't currently seem worth expending extra
880 : * effort to do so.)
881 : */
882 15496098 : else if (IsA(node, WindowFunc))
883 : {
884 6084 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
885 2660 : return true;
886 : }
887 :
888 : /*
889 : * As a notational convenience for callers, look through RestrictInfo.
890 : */
891 15490014 : else if (IsA(node, RestrictInfo))
892 : {
893 253020 : RestrictInfo *rinfo = (RestrictInfo *) node;
894 :
895 253020 : return max_parallel_hazard_walker((Node *) rinfo->clause, context);
896 : }
897 :
898 : /*
899 : * Really we should not see SubLink during a max_interesting == restricted
900 : * scan, but if we do, return true.
901 : */
902 15236994 : else if (IsA(node, SubLink))
903 : {
904 41002 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
905 0 : return true;
906 : }
907 :
908 : /*
909 : * Only parallel-safe SubPlans can be sent to workers. Within the
910 : * testexpr of the SubPlan, Params representing the output columns of the
911 : * subplan can be treated as parallel-safe, so temporarily add their IDs
912 : * to the safe_param_ids list while examining the testexpr.
913 : */
914 15195992 : else if (IsA(node, SubPlan))
915 : {
916 31576 : SubPlan *subplan = (SubPlan *) node;
917 : List *save_safe_param_ids;
918 :
919 62822 : if (!subplan->parallel_safe &&
920 31246 : max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
921 31246 : return true;
922 330 : save_safe_param_ids = context->safe_param_ids;
923 660 : context->safe_param_ids = list_concat_copy(context->safe_param_ids,
924 330 : subplan->paramIds);
925 330 : if (max_parallel_hazard_walker(subplan->testexpr, context))
926 6 : return true; /* no need to restore safe_param_ids */
927 324 : list_free(context->safe_param_ids);
928 324 : context->safe_param_ids = save_safe_param_ids;
929 : /* we must also check args, but no special Param treatment there */
930 324 : if (max_parallel_hazard_walker((Node *) subplan->args, context))
931 0 : return true;
932 : /* don't want to recurse normally, so we're done */
933 324 : return false;
934 : }
935 :
936 : /*
937 : * We can't pass Params to workers at the moment either, so they are also
938 : * parallel-restricted, unless they are PARAM_EXTERN Params or are
939 : * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
940 : * either generated within workers or can be computed by the leader and
941 : * then their value can be passed to workers.
942 : */
943 15164416 : else if (IsA(node, Param))
944 : {
945 111044 : Param *param = (Param *) node;
946 :
947 111044 : if (param->paramkind == PARAM_EXTERN)
948 58088 : return false;
949 :
950 52956 : if (param->paramkind != PARAM_EXEC ||
951 47938 : !list_member_int(context->safe_param_ids, param->paramid))
952 : {
953 42186 : if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
954 37234 : return true;
955 : }
956 15722 : return false; /* nothing to recurse to */
957 : }
958 :
959 : /*
960 : * When we're first invoked on a completely unplanned tree, we must
961 : * recurse into subqueries so to as to locate parallel-unsafe constructs
962 : * anywhere in the tree.
963 : */
964 15053372 : else if (IsA(node, Query))
965 : {
966 458144 : Query *query = (Query *) node;
967 :
968 : /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
969 458144 : if (query->rowMarks != NULL)
970 : {
971 7392 : context->max_hazard = PROPARALLEL_UNSAFE;
972 7392 : return true;
973 : }
974 :
975 : /* Recurse into subselects */
976 450752 : return query_tree_walker(query,
977 : max_parallel_hazard_walker,
978 : context, 0);
979 : }
980 :
981 : /* Recurse to check arguments */
982 14652898 : return expression_tree_walker(node,
983 : max_parallel_hazard_walker,
984 : context);
985 : }
986 :
987 :
988 : /*****************************************************************************
989 : * Check clauses for nonstrict functions
990 : *****************************************************************************/
991 :
992 : /*
993 : * contain_nonstrict_functions
994 : * Recursively search for nonstrict functions within a clause.
995 : *
996 : * Returns true if any nonstrict construct is found --- ie, anything that
997 : * could produce non-NULL output with a NULL input.
998 : *
999 : * The idea here is that the caller has verified that the expression contains
1000 : * one or more Var or Param nodes (as appropriate for the caller's need), and
1001 : * now wishes to prove that the expression result will be NULL if any of these
1002 : * inputs is NULL. If we return false, then the proof succeeded.
1003 : */
1004 : bool
1005 2398 : contain_nonstrict_functions(Node *clause)
1006 : {
1007 2398 : return contain_nonstrict_functions_walker(clause, NULL);
1008 : }
1009 :
1010 : static bool
1011 2490 : contain_nonstrict_functions_checker(Oid func_id, void *context)
1012 : {
1013 2490 : return !func_strict(func_id);
1014 : }
1015 :
1016 : static bool
1017 8398 : contain_nonstrict_functions_walker(Node *node, void *context)
1018 : {
1019 8398 : if (node == NULL)
1020 0 : return false;
1021 8398 : if (IsA(node, Aggref))
1022 : {
1023 : /* an aggregate could return non-null with null input */
1024 0 : return true;
1025 : }
1026 8398 : if (IsA(node, GroupingFunc))
1027 : {
1028 : /*
1029 : * A GroupingFunc doesn't evaluate its arguments, and therefore must
1030 : * be treated as nonstrict.
1031 : */
1032 0 : return true;
1033 : }
1034 8398 : if (IsA(node, WindowFunc))
1035 : {
1036 : /* a window function could return non-null with null input */
1037 0 : return true;
1038 : }
1039 8398 : if (IsA(node, SubscriptingRef))
1040 : {
1041 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1042 : const SubscriptRoutines *sbsroutines;
1043 :
1044 : /* Subscripting assignment is always presumed nonstrict */
1045 0 : if (sbsref->refassgnexpr != NULL)
1046 0 : return true;
1047 : /* Otherwise we must look up the subscripting support methods */
1048 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
1049 0 : if (!(sbsroutines && sbsroutines->fetch_strict))
1050 0 : return true;
1051 : /* else fall through to check args */
1052 : }
1053 8398 : if (IsA(node, DistinctExpr))
1054 : {
1055 : /* IS DISTINCT FROM is inherently non-strict */
1056 0 : return true;
1057 : }
1058 8398 : if (IsA(node, NullIfExpr))
1059 : {
1060 : /* NULLIF is inherently non-strict */
1061 0 : return true;
1062 : }
1063 8398 : if (IsA(node, BoolExpr))
1064 : {
1065 18 : BoolExpr *expr = (BoolExpr *) node;
1066 :
1067 18 : switch (expr->boolop)
1068 : {
1069 18 : case AND_EXPR:
1070 : case OR_EXPR:
1071 : /* AND, OR are inherently non-strict */
1072 18 : return true;
1073 0 : default:
1074 0 : break;
1075 : }
1076 : }
1077 8380 : if (IsA(node, SubLink))
1078 : {
1079 : /* In some cases a sublink might be strict, but in general not */
1080 12 : return true;
1081 : }
1082 8368 : if (IsA(node, SubPlan))
1083 0 : return true;
1084 8368 : if (IsA(node, AlternativeSubPlan))
1085 0 : return true;
1086 8368 : if (IsA(node, FieldStore))
1087 0 : return true;
1088 8368 : if (IsA(node, CoerceViaIO))
1089 : {
1090 : /*
1091 : * CoerceViaIO is strict regardless of whether the I/O functions are,
1092 : * so just go look at its argument; asking check_functions_in_node is
1093 : * useless expense and could deliver the wrong answer.
1094 : */
1095 1096 : return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
1096 : context);
1097 : }
1098 7272 : if (IsA(node, ArrayCoerceExpr))
1099 : {
1100 : /*
1101 : * ArrayCoerceExpr is strict at the array level, regardless of what
1102 : * the per-element expression is; so we should ignore elemexpr and
1103 : * recurse only into the arg.
1104 : */
1105 0 : return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
1106 : context);
1107 : }
1108 7272 : if (IsA(node, CaseExpr))
1109 64 : return true;
1110 7208 : if (IsA(node, ArrayExpr))
1111 0 : return true;
1112 7208 : if (IsA(node, RowExpr))
1113 4 : return true;
1114 7204 : if (IsA(node, RowCompareExpr))
1115 0 : return true;
1116 7204 : if (IsA(node, CoalesceExpr))
1117 254 : return true;
1118 6950 : if (IsA(node, MinMaxExpr))
1119 60 : return true;
1120 6890 : if (IsA(node, XmlExpr))
1121 0 : return true;
1122 6890 : if (IsA(node, NullTest))
1123 24 : return true;
1124 6866 : if (IsA(node, BooleanTest))
1125 0 : return true;
1126 6866 : if (IsA(node, JsonConstructorExpr))
1127 12 : return true;
1128 :
1129 : /* Check other function-containing nodes */
1130 6854 : if (check_functions_in_node(node, contain_nonstrict_functions_checker,
1131 : context))
1132 0 : return true;
1133 :
1134 6854 : return expression_tree_walker(node, contain_nonstrict_functions_walker,
1135 : context);
1136 : }
1137 :
1138 : /*****************************************************************************
1139 : * Check clauses for Params
1140 : *****************************************************************************/
1141 :
1142 : /*
1143 : * contain_exec_param
1144 : * Recursively search for PARAM_EXEC Params within a clause.
1145 : *
1146 : * Returns true if the clause contains any PARAM_EXEC Param with a paramid
1147 : * appearing in the given list of Param IDs. Does not descend into
1148 : * subqueries!
1149 : */
1150 : bool
1151 3006 : contain_exec_param(Node *clause, List *param_ids)
1152 : {
1153 3006 : return contain_exec_param_walker(clause, param_ids);
1154 : }
1155 :
1156 : static bool
1157 3294 : contain_exec_param_walker(Node *node, List *param_ids)
1158 : {
1159 3294 : if (node == NULL)
1160 36 : return false;
1161 3258 : if (IsA(node, Param))
1162 : {
1163 12 : Param *p = (Param *) node;
1164 :
1165 24 : if (p->paramkind == PARAM_EXEC &&
1166 12 : list_member_int(param_ids, p->paramid))
1167 12 : return true;
1168 : }
1169 3246 : return expression_tree_walker(node, contain_exec_param_walker, param_ids);
1170 : }
1171 :
1172 : /*****************************************************************************
1173 : * Check clauses for context-dependent nodes
1174 : *****************************************************************************/
1175 :
1176 : /*
1177 : * contain_context_dependent_node
1178 : * Recursively search for context-dependent nodes within a clause.
1179 : *
1180 : * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
1181 : * not nested within another one, or they'll see the wrong test value. If one
1182 : * appears "bare" in the arguments of a SQL function, then we can't inline the
1183 : * SQL function for fear of creating such a situation. The same applies for
1184 : * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
1185 : *
1186 : * CoerceToDomainValue would have the same issue if domain CHECK expressions
1187 : * could get inlined into larger expressions, but presently that's impossible.
1188 : * Still, it might be allowed in future, or other node types with similar
1189 : * issues might get invented. So give this function a generic name, and set
1190 : * up the recursion state to allow multiple flag bits.
1191 : */
1192 : static bool
1193 3278 : contain_context_dependent_node(Node *clause)
1194 : {
1195 3278 : int flags = 0;
1196 :
1197 3278 : return contain_context_dependent_node_walker(clause, &flags);
1198 : }
1199 :
1200 : #define CCDN_CASETESTEXPR_OK 0x0001 /* CaseTestExpr okay here? */
1201 :
1202 : static bool
1203 10012 : contain_context_dependent_node_walker(Node *node, int *flags)
1204 : {
1205 10012 : if (node == NULL)
1206 194 : return false;
1207 9818 : if (IsA(node, CaseTestExpr))
1208 6 : return !(*flags & CCDN_CASETESTEXPR_OK);
1209 9812 : else if (IsA(node, CaseExpr))
1210 : {
1211 0 : CaseExpr *caseexpr = (CaseExpr *) node;
1212 :
1213 : /*
1214 : * If this CASE doesn't have a test expression, then it doesn't create
1215 : * a context in which CaseTestExprs should appear, so just fall
1216 : * through and treat it as a generic expression node.
1217 : */
1218 0 : if (caseexpr->arg)
1219 : {
1220 0 : int save_flags = *flags;
1221 : bool res;
1222 :
1223 : /*
1224 : * Note: in principle, we could distinguish the various sub-parts
1225 : * of a CASE construct and set the flag bit only for some of them,
1226 : * since we are only expecting CaseTestExprs to appear in the
1227 : * "expr" subtree of the CaseWhen nodes. But it doesn't really
1228 : * seem worth any extra code. If there are any bare CaseTestExprs
1229 : * elsewhere in the CASE, something's wrong already.
1230 : */
1231 0 : *flags |= CCDN_CASETESTEXPR_OK;
1232 0 : res = expression_tree_walker(node,
1233 : contain_context_dependent_node_walker,
1234 : flags);
1235 0 : *flags = save_flags;
1236 0 : return res;
1237 : }
1238 : }
1239 9812 : else if (IsA(node, ArrayCoerceExpr))
1240 : {
1241 0 : ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
1242 : int save_flags;
1243 : bool res;
1244 :
1245 : /* Check the array expression */
1246 0 : if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
1247 0 : return true;
1248 :
1249 : /* Check the elemexpr, which is allowed to contain CaseTestExpr */
1250 0 : save_flags = *flags;
1251 0 : *flags |= CCDN_CASETESTEXPR_OK;
1252 0 : res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
1253 : flags);
1254 0 : *flags = save_flags;
1255 0 : return res;
1256 : }
1257 9812 : return expression_tree_walker(node, contain_context_dependent_node_walker,
1258 : flags);
1259 : }
1260 :
1261 : /*****************************************************************************
1262 : * Check clauses for Vars passed to non-leakproof functions
1263 : *****************************************************************************/
1264 :
1265 : /*
1266 : * contain_leaked_vars
1267 : * Recursively scan a clause to discover whether it contains any Var
1268 : * nodes (of the current query level) that are passed as arguments to
1269 : * leaky functions.
1270 : *
1271 : * Returns true if the clause contains any non-leakproof functions that are
1272 : * passed Var nodes of the current query level, and which might therefore leak
1273 : * data. Such clauses must be applied after any lower-level security barrier
1274 : * clauses.
1275 : */
1276 : bool
1277 6258 : contain_leaked_vars(Node *clause)
1278 : {
1279 6258 : return contain_leaked_vars_walker(clause, NULL);
1280 : }
1281 :
1282 : static bool
1283 6230 : contain_leaked_vars_checker(Oid func_id, void *context)
1284 : {
1285 6230 : return !get_func_leakproof(func_id);
1286 : }
1287 :
1288 : static bool
1289 13324 : contain_leaked_vars_walker(Node *node, void *context)
1290 : {
1291 13324 : if (node == NULL)
1292 0 : return false;
1293 :
1294 13324 : switch (nodeTag(node))
1295 : {
1296 7022 : case T_Var:
1297 : case T_Const:
1298 : case T_Param:
1299 : case T_ArrayExpr:
1300 : case T_FieldSelect:
1301 : case T_FieldStore:
1302 : case T_NamedArgExpr:
1303 : case T_BoolExpr:
1304 : case T_RelabelType:
1305 : case T_CollateExpr:
1306 : case T_CaseExpr:
1307 : case T_CaseTestExpr:
1308 : case T_RowExpr:
1309 : case T_SQLValueFunction:
1310 : case T_NullTest:
1311 : case T_BooleanTest:
1312 : case T_NextValueExpr:
1313 : case T_ReturningExpr:
1314 : case T_List:
1315 :
1316 : /*
1317 : * We know these node types don't contain function calls; but
1318 : * something further down in the node tree might.
1319 : */
1320 7022 : break;
1321 :
1322 6230 : case T_FuncExpr:
1323 : case T_OpExpr:
1324 : case T_DistinctExpr:
1325 : case T_NullIfExpr:
1326 : case T_ScalarArrayOpExpr:
1327 : case T_CoerceViaIO:
1328 : case T_ArrayCoerceExpr:
1329 :
1330 : /*
1331 : * If node contains a leaky function call, and there's any Var
1332 : * underneath it, reject.
1333 : */
1334 6230 : if (check_functions_in_node(node, contain_leaked_vars_checker,
1335 2702 : context) &&
1336 2702 : contain_var_clause(node))
1337 2646 : return true;
1338 3584 : break;
1339 :
1340 0 : case T_SubscriptingRef:
1341 : {
1342 0 : SubscriptingRef *sbsref = (SubscriptingRef *) node;
1343 : const SubscriptRoutines *sbsroutines;
1344 :
1345 : /* Consult the subscripting support method info */
1346 0 : sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
1347 : NULL);
1348 0 : if (!sbsroutines ||
1349 0 : !(sbsref->refassgnexpr != NULL ?
1350 0 : sbsroutines->store_leakproof :
1351 0 : sbsroutines->fetch_leakproof))
1352 : {
1353 : /* Node is leaky, so reject if it contains Vars */
1354 0 : if (contain_var_clause(node))
1355 0 : return true;
1356 : }
1357 : }
1358 0 : break;
1359 :
1360 0 : case T_RowCompareExpr:
1361 : {
1362 : /*
1363 : * It's worth special-casing this because a leaky comparison
1364 : * function only compromises one pair of row elements, which
1365 : * might not contain Vars while others do.
1366 : */
1367 0 : RowCompareExpr *rcexpr = (RowCompareExpr *) node;
1368 : ListCell *opid;
1369 : ListCell *larg;
1370 : ListCell *rarg;
1371 :
1372 0 : forthree(opid, rcexpr->opnos,
1373 : larg, rcexpr->largs,
1374 : rarg, rcexpr->rargs)
1375 : {
1376 0 : Oid funcid = get_opcode(lfirst_oid(opid));
1377 :
1378 0 : if (!get_func_leakproof(funcid) &&
1379 0 : (contain_var_clause((Node *) lfirst(larg)) ||
1380 0 : contain_var_clause((Node *) lfirst(rarg))))
1381 0 : return true;
1382 : }
1383 : }
1384 0 : break;
1385 :
1386 0 : case T_MinMaxExpr:
1387 : {
1388 : /*
1389 : * MinMaxExpr is leakproof if the comparison function it calls
1390 : * is leakproof.
1391 : */
1392 0 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
1393 : TypeCacheEntry *typentry;
1394 : bool leakproof;
1395 :
1396 : /* Look up the btree comparison function for the datatype */
1397 0 : typentry = lookup_type_cache(minmaxexpr->minmaxtype,
1398 : TYPECACHE_CMP_PROC);
1399 0 : if (OidIsValid(typentry->cmp_proc))
1400 0 : leakproof = get_func_leakproof(typentry->cmp_proc);
1401 : else
1402 : {
1403 : /*
1404 : * The executor will throw an error, but here we just
1405 : * treat the missing function as leaky.
1406 : */
1407 0 : leakproof = false;
1408 : }
1409 :
1410 0 : if (!leakproof &&
1411 0 : contain_var_clause((Node *) minmaxexpr->args))
1412 0 : return true;
1413 : }
1414 0 : break;
1415 :
1416 42 : case T_CurrentOfExpr:
1417 :
1418 : /*
1419 : * WHERE CURRENT OF doesn't contain leaky function calls.
1420 : * Moreover, it is essential that this is considered non-leaky,
1421 : * since the planner must always generate a TID scan when CURRENT
1422 : * OF is present -- cf. cost_tidscan.
1423 : */
1424 42 : return false;
1425 :
1426 30 : default:
1427 :
1428 : /*
1429 : * If we don't recognize the node tag, assume it might be leaky.
1430 : * This prevents an unexpected security hole if someone adds a new
1431 : * node type that can call a function.
1432 : */
1433 30 : return true;
1434 : }
1435 10606 : return expression_tree_walker(node, contain_leaked_vars_walker,
1436 : context);
1437 : }
1438 :
1439 : /*
1440 : * find_nonnullable_rels
1441 : * Determine which base rels are forced nonnullable by given clause.
1442 : *
1443 : * Returns the set of all Relids that are referenced in the clause in such
1444 : * a way that the clause cannot possibly return TRUE if any of these Relids
1445 : * is an all-NULL row. (It is OK to err on the side of conservatism; hence
1446 : * the analysis here is simplistic.)
1447 : *
1448 : * The semantics here are subtly different from contain_nonstrict_functions:
1449 : * that function is concerned with NULL results from arbitrary expressions,
1450 : * but here we assume that the input is a Boolean expression, and wish to
1451 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1452 : * the expression to have been AND/OR flattened and converted to implicit-AND
1453 : * format.
1454 : *
1455 : * Note: this function is largely duplicative of find_nonnullable_vars().
1456 : * The reason not to simplify this function into a thin wrapper around
1457 : * find_nonnullable_vars() is that the tested conditions really are different:
1458 : * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
1459 : * that either v1 or v2 can't be NULL, but it does prove that the t1 row
1460 : * as a whole can't be all-NULL. Also, the behavior for PHVs is different.
1461 : *
1462 : * top_level is true while scanning top-level AND/OR structure; here, showing
1463 : * the result is either FALSE or NULL is good enough. top_level is false when
1464 : * we have descended below a NOT or a strict function: now we must be able to
1465 : * prove that the subexpression goes to NULL.
1466 : *
1467 : * We don't use expression_tree_walker here because we don't want to descend
1468 : * through very many kinds of nodes; only the ones we can be sure are strict.
1469 : */
1470 : Relids
1471 105610 : find_nonnullable_rels(Node *clause)
1472 : {
1473 105610 : return find_nonnullable_rels_walker(clause, true);
1474 : }
1475 :
1476 : static Relids
1477 687796 : find_nonnullable_rels_walker(Node *node, bool top_level)
1478 : {
1479 687796 : Relids result = NULL;
1480 : ListCell *l;
1481 :
1482 687796 : if (node == NULL)
1483 6578 : return NULL;
1484 681218 : if (IsA(node, Var))
1485 : {
1486 219832 : Var *var = (Var *) node;
1487 :
1488 219832 : if (var->varlevelsup == 0)
1489 219832 : result = bms_make_singleton(var->varno);
1490 : }
1491 461386 : else if (IsA(node, List))
1492 : {
1493 : /*
1494 : * At top level, we are examining an implicit-AND list: if any of the
1495 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1496 : * not at top level, we are examining the arguments of a strict
1497 : * function: if any of them produce NULL then the result of the
1498 : * function must be NULL. So in both cases, the set of nonnullable
1499 : * rels is the union of those found in the arms, and we pass down the
1500 : * top_level flag unmodified.
1501 : */
1502 665406 : foreach(l, (List *) node)
1503 : {
1504 422450 : result = bms_join(result,
1505 422450 : find_nonnullable_rels_walker(lfirst(l),
1506 : top_level));
1507 : }
1508 : }
1509 218430 : else if (IsA(node, FuncExpr))
1510 : {
1511 7334 : FuncExpr *expr = (FuncExpr *) node;
1512 :
1513 7334 : if (func_strict(expr->funcid))
1514 7142 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1515 : }
1516 211096 : else if (IsA(node, OpExpr))
1517 : {
1518 123912 : OpExpr *expr = (OpExpr *) node;
1519 :
1520 123912 : set_opfuncid(expr);
1521 123912 : if (func_strict(expr->opfuncid))
1522 123912 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1523 : }
1524 87184 : else if (IsA(node, ScalarArrayOpExpr))
1525 : {
1526 9132 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1527 :
1528 9132 : if (is_strict_saop(expr, true))
1529 9132 : result = find_nonnullable_rels_walker((Node *) expr->args, false);
1530 : }
1531 78052 : else if (IsA(node, BoolExpr))
1532 : {
1533 7664 : BoolExpr *expr = (BoolExpr *) node;
1534 :
1535 7664 : switch (expr->boolop)
1536 : {
1537 470 : case AND_EXPR:
1538 : /* At top level we can just recurse (to the List case) */
1539 470 : if (top_level)
1540 : {
1541 470 : result = find_nonnullable_rels_walker((Node *) expr->args,
1542 : top_level);
1543 470 : break;
1544 : }
1545 :
1546 : /*
1547 : * Below top level, even if one arm produces NULL, the result
1548 : * could be FALSE (hence not NULL). However, if *all* the
1549 : * arms produce NULL then the result is NULL, so we can take
1550 : * the intersection of the sets of nonnullable rels, just as
1551 : * for OR. Fall through to share code.
1552 : */
1553 : /* FALL THRU */
1554 : case OR_EXPR:
1555 :
1556 : /*
1557 : * OR is strict if all of its arms are, so we can take the
1558 : * intersection of the sets of nonnullable rels for each arm.
1559 : * This works for both values of top_level.
1560 : */
1561 8922 : foreach(l, expr->args)
1562 : {
1563 : Relids subresult;
1564 :
1565 7786 : subresult = find_nonnullable_rels_walker(lfirst(l),
1566 : top_level);
1567 7786 : if (result == NULL) /* first subresult? */
1568 3926 : result = subresult;
1569 : else
1570 3860 : result = bms_int_members(result, subresult);
1571 :
1572 : /*
1573 : * If the intersection is empty, we can stop looking. This
1574 : * also justifies the test for first-subresult above.
1575 : */
1576 7786 : if (bms_is_empty(result))
1577 2790 : break;
1578 : }
1579 3926 : break;
1580 3268 : case NOT_EXPR:
1581 : /* NOT will return null if its arg is null */
1582 3268 : result = find_nonnullable_rels_walker((Node *) expr->args,
1583 : false);
1584 3268 : break;
1585 0 : default:
1586 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1587 : break;
1588 : }
1589 : }
1590 70388 : else if (IsA(node, RelabelType))
1591 : {
1592 4232 : RelabelType *expr = (RelabelType *) node;
1593 :
1594 4232 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1595 : }
1596 66156 : else if (IsA(node, CoerceViaIO))
1597 : {
1598 : /* not clear this is useful, but it can't hurt */
1599 208 : CoerceViaIO *expr = (CoerceViaIO *) node;
1600 :
1601 208 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1602 : }
1603 65948 : else if (IsA(node, ArrayCoerceExpr))
1604 : {
1605 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1606 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1607 :
1608 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1609 : }
1610 65948 : else if (IsA(node, ConvertRowtypeExpr))
1611 : {
1612 : /* not clear this is useful, but it can't hurt */
1613 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1614 :
1615 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1616 : }
1617 65948 : else if (IsA(node, CollateExpr))
1618 : {
1619 0 : CollateExpr *expr = (CollateExpr *) node;
1620 :
1621 0 : result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
1622 : }
1623 65948 : else if (IsA(node, NullTest))
1624 : {
1625 : /* IS NOT NULL can be considered strict, but only at top level */
1626 4688 : NullTest *expr = (NullTest *) node;
1627 :
1628 4688 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1629 2896 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1630 : }
1631 61260 : else if (IsA(node, BooleanTest))
1632 : {
1633 : /* Boolean tests that reject NULL are strict at top level */
1634 106 : BooleanTest *expr = (BooleanTest *) node;
1635 :
1636 106 : if (top_level &&
1637 106 : (expr->booltesttype == IS_TRUE ||
1638 106 : expr->booltesttype == IS_FALSE ||
1639 6 : expr->booltesttype == IS_NOT_UNKNOWN))
1640 100 : result = find_nonnullable_rels_walker((Node *) expr->arg, false);
1641 : }
1642 61154 : else if (IsA(node, SubPlan))
1643 : {
1644 126 : SubPlan *splan = (SubPlan *) node;
1645 :
1646 : /*
1647 : * For some types of SubPlan, we can infer strictness from Vars in the
1648 : * testexpr (the LHS of the original SubLink).
1649 : *
1650 : * For ANY_SUBLINK, if the subquery produces zero rows, the result is
1651 : * always FALSE. If the subquery produces more than one row, the
1652 : * per-row results of the testexpr are combined using OR semantics.
1653 : * Hence ANY_SUBLINK can be strict only at top level, but there it's
1654 : * as strict as the testexpr is.
1655 : *
1656 : * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
1657 : * result is always NULL. Otherwise, the result is as strict as the
1658 : * testexpr is. So we can check regardless of top_level.
1659 : *
1660 : * We can't prove anything for other sublink types (in particular,
1661 : * note that ALL_SUBLINK will return TRUE if the subquery is empty).
1662 : */
1663 126 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1664 84 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1665 42 : result = find_nonnullable_rels_walker(splan->testexpr, top_level);
1666 : }
1667 61028 : else if (IsA(node, PlaceHolderVar))
1668 : {
1669 548 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1670 :
1671 : /*
1672 : * If the contained expression forces any rels non-nullable, so does
1673 : * the PHV.
1674 : */
1675 548 : result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
1676 :
1677 : /*
1678 : * If the PHV's syntactic scope is exactly one rel, it will be forced
1679 : * to be evaluated at that rel, and so it will behave like a Var of
1680 : * that rel: if the rel's entire output goes to null, so will the PHV.
1681 : * (If the syntactic scope is a join, we know that the PHV will go to
1682 : * null if the whole join does; but that is AND semantics while we
1683 : * need OR semantics for find_nonnullable_rels' result, so we can't do
1684 : * anything with the knowledge.)
1685 : */
1686 1096 : if (phv->phlevelsup == 0 &&
1687 548 : bms_membership(phv->phrels) == BMS_SINGLETON)
1688 356 : result = bms_add_members(result, phv->phrels);
1689 : }
1690 681218 : return result;
1691 : }
1692 :
1693 : /*
1694 : * find_nonnullable_vars
1695 : * Determine which Vars are forced nonnullable by given clause.
1696 : *
1697 : * Returns the set of all level-zero Vars that are referenced in the clause in
1698 : * such a way that the clause cannot possibly return TRUE if any of these Vars
1699 : * is NULL. (It is OK to err on the side of conservatism; hence the analysis
1700 : * here is simplistic.)
1701 : *
1702 : * The semantics here are subtly different from contain_nonstrict_functions:
1703 : * that function is concerned with NULL results from arbitrary expressions,
1704 : * but here we assume that the input is a Boolean expression, and wish to
1705 : * see if NULL inputs will provably cause a FALSE-or-NULL result. We expect
1706 : * the expression to have been AND/OR flattened and converted to implicit-AND
1707 : * format.
1708 : *
1709 : * Attnos of the identified Vars are returned in a multibitmapset (a List of
1710 : * Bitmapsets). List indexes correspond to relids (varnos), while the per-rel
1711 : * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
1712 : *
1713 : * top_level is true while scanning top-level AND/OR structure; here, showing
1714 : * the result is either FALSE or NULL is good enough. top_level is false when
1715 : * we have descended below a NOT or a strict function: now we must be able to
1716 : * prove that the subexpression goes to NULL.
1717 : *
1718 : * We don't use expression_tree_walker here because we don't want to descend
1719 : * through very many kinds of nodes; only the ones we can be sure are strict.
1720 : */
1721 : List *
1722 46092 : find_nonnullable_vars(Node *clause)
1723 : {
1724 46092 : return find_nonnullable_vars_walker(clause, true);
1725 : }
1726 :
1727 : static List *
1728 294564 : find_nonnullable_vars_walker(Node *node, bool top_level)
1729 : {
1730 294564 : List *result = NIL;
1731 : ListCell *l;
1732 :
1733 294564 : if (node == NULL)
1734 680 : return NIL;
1735 293884 : if (IsA(node, Var))
1736 : {
1737 109130 : Var *var = (Var *) node;
1738 :
1739 109130 : if (var->varlevelsup == 0)
1740 109130 : result = mbms_add_member(result,
1741 : var->varno,
1742 109130 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1743 : }
1744 184754 : else if (IsA(node, List))
1745 : {
1746 : /*
1747 : * At top level, we are examining an implicit-AND list: if any of the
1748 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
1749 : * not at top level, we are examining the arguments of a strict
1750 : * function: if any of them produce NULL then the result of the
1751 : * function must be NULL. So in both cases, the set of nonnullable
1752 : * vars is the union of those found in the arms, and we pass down the
1753 : * top_level flag unmodified.
1754 : */
1755 292310 : foreach(l, (List *) node)
1756 : {
1757 184878 : result = mbms_add_members(result,
1758 184878 : find_nonnullable_vars_walker(lfirst(l),
1759 : top_level));
1760 : }
1761 : }
1762 77322 : else if (IsA(node, FuncExpr))
1763 : {
1764 446 : FuncExpr *expr = (FuncExpr *) node;
1765 :
1766 446 : if (func_strict(expr->funcid))
1767 422 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1768 : }
1769 76876 : else if (IsA(node, OpExpr))
1770 : {
1771 59790 : OpExpr *expr = (OpExpr *) node;
1772 :
1773 59790 : set_opfuncid(expr);
1774 59790 : if (func_strict(expr->opfuncid))
1775 59790 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1776 : }
1777 17086 : else if (IsA(node, ScalarArrayOpExpr))
1778 : {
1779 1744 : ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
1780 :
1781 1744 : if (is_strict_saop(expr, true))
1782 1744 : result = find_nonnullable_vars_walker((Node *) expr->args, false);
1783 : }
1784 15342 : else if (IsA(node, BoolExpr))
1785 : {
1786 382 : BoolExpr *expr = (BoolExpr *) node;
1787 :
1788 382 : switch (expr->boolop)
1789 : {
1790 0 : case AND_EXPR:
1791 :
1792 : /*
1793 : * At top level we can just recurse (to the List case), since
1794 : * the result should be the union of what we can prove in each
1795 : * arm.
1796 : */
1797 0 : if (top_level)
1798 : {
1799 0 : result = find_nonnullable_vars_walker((Node *) expr->args,
1800 : top_level);
1801 0 : break;
1802 : }
1803 :
1804 : /*
1805 : * Below top level, even if one arm produces NULL, the result
1806 : * could be FALSE (hence not NULL). However, if *all* the
1807 : * arms produce NULL then the result is NULL, so we can take
1808 : * the intersection of the sets of nonnullable vars, just as
1809 : * for OR. Fall through to share code.
1810 : */
1811 : /* FALL THRU */
1812 : case OR_EXPR:
1813 :
1814 : /*
1815 : * OR is strict if all of its arms are, so we can take the
1816 : * intersection of the sets of nonnullable vars for each arm.
1817 : * This works for both values of top_level.
1818 : */
1819 832 : foreach(l, expr->args)
1820 : {
1821 : List *subresult;
1822 :
1823 676 : subresult = find_nonnullable_vars_walker(lfirst(l),
1824 : top_level);
1825 676 : if (result == NIL) /* first subresult? */
1826 318 : result = subresult;
1827 : else
1828 358 : result = mbms_int_members(result, subresult);
1829 :
1830 : /*
1831 : * If the intersection is empty, we can stop looking. This
1832 : * also justifies the test for first-subresult above.
1833 : */
1834 676 : if (result == NIL)
1835 162 : break;
1836 : }
1837 318 : break;
1838 64 : case NOT_EXPR:
1839 : /* NOT will return null if its arg is null */
1840 64 : result = find_nonnullable_vars_walker((Node *) expr->args,
1841 : false);
1842 64 : break;
1843 0 : default:
1844 0 : elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
1845 : break;
1846 : }
1847 : }
1848 14960 : else if (IsA(node, RelabelType))
1849 : {
1850 600 : RelabelType *expr = (RelabelType *) node;
1851 :
1852 600 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1853 : }
1854 14360 : else if (IsA(node, CoerceViaIO))
1855 : {
1856 : /* not clear this is useful, but it can't hurt */
1857 118 : CoerceViaIO *expr = (CoerceViaIO *) node;
1858 :
1859 118 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1860 : }
1861 14242 : else if (IsA(node, ArrayCoerceExpr))
1862 : {
1863 : /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
1864 0 : ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
1865 :
1866 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1867 : }
1868 14242 : else if (IsA(node, ConvertRowtypeExpr))
1869 : {
1870 : /* not clear this is useful, but it can't hurt */
1871 0 : ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
1872 :
1873 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1874 : }
1875 14242 : else if (IsA(node, CollateExpr))
1876 : {
1877 0 : CollateExpr *expr = (CollateExpr *) node;
1878 :
1879 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
1880 : }
1881 14242 : else if (IsA(node, NullTest))
1882 : {
1883 : /* IS NOT NULL can be considered strict, but only at top level */
1884 276 : NullTest *expr = (NullTest *) node;
1885 :
1886 276 : if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
1887 96 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1888 : }
1889 13966 : else if (IsA(node, BooleanTest))
1890 : {
1891 : /* Boolean tests that reject NULL are strict at top level */
1892 0 : BooleanTest *expr = (BooleanTest *) node;
1893 :
1894 0 : if (top_level &&
1895 0 : (expr->booltesttype == IS_TRUE ||
1896 0 : expr->booltesttype == IS_FALSE ||
1897 0 : expr->booltesttype == IS_NOT_UNKNOWN))
1898 0 : result = find_nonnullable_vars_walker((Node *) expr->arg, false);
1899 : }
1900 13966 : else if (IsA(node, SubPlan))
1901 : {
1902 30 : SubPlan *splan = (SubPlan *) node;
1903 :
1904 : /* See analysis in find_nonnullable_rels_walker */
1905 30 : if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
1906 6 : splan->subLinkType == ROWCOMPARE_SUBLINK)
1907 24 : result = find_nonnullable_vars_walker(splan->testexpr, top_level);
1908 : }
1909 13936 : else if (IsA(node, PlaceHolderVar))
1910 : {
1911 60 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
1912 :
1913 60 : result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
1914 : }
1915 293884 : return result;
1916 : }
1917 :
1918 : /*
1919 : * find_forced_null_vars
1920 : * Determine which Vars must be NULL for the given clause to return TRUE.
1921 : *
1922 : * This is the complement of find_nonnullable_vars: find the level-zero Vars
1923 : * that must be NULL for the clause to return TRUE. (It is OK to err on the
1924 : * side of conservatism; hence the analysis here is simplistic. In fact,
1925 : * we only detect simple "var IS NULL" tests at the top level.)
1926 : *
1927 : * As with find_nonnullable_vars, we return the varattnos of the identified
1928 : * Vars in a multibitmapset.
1929 : */
1930 : List *
1931 123372 : find_forced_null_vars(Node *node)
1932 : {
1933 123372 : List *result = NIL;
1934 : Var *var;
1935 : ListCell *l;
1936 :
1937 123372 : if (node == NULL)
1938 5744 : return NIL;
1939 : /* Check single-clause cases using subroutine */
1940 117628 : var = find_forced_null_var(node);
1941 117628 : if (var)
1942 : {
1943 1342 : result = mbms_add_member(result,
1944 : var->varno,
1945 1342 : var->varattno - FirstLowInvalidHeapAttributeNumber);
1946 : }
1947 : /* Otherwise, handle AND-conditions */
1948 116286 : else if (IsA(node, List))
1949 : {
1950 : /*
1951 : * At top level, we are examining an implicit-AND list: if any of the
1952 : * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
1953 : */
1954 117628 : foreach(l, (List *) node)
1955 : {
1956 71700 : result = mbms_add_members(result,
1957 71700 : find_forced_null_vars((Node *) lfirst(l)));
1958 : }
1959 : }
1960 70358 : else if (IsA(node, BoolExpr))
1961 : {
1962 5518 : BoolExpr *expr = (BoolExpr *) node;
1963 :
1964 : /*
1965 : * We don't bother considering the OR case, because it's fairly
1966 : * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
1967 : * the NOT case isn't worth expending code on.
1968 : */
1969 5518 : if (expr->boolop == AND_EXPR)
1970 : {
1971 : /* At top level we can just recurse (to the List case) */
1972 0 : result = find_forced_null_vars((Node *) expr->args);
1973 : }
1974 : }
1975 117628 : return result;
1976 : }
1977 :
1978 : /*
1979 : * find_forced_null_var
1980 : * Return the Var forced null by the given clause, or NULL if it's
1981 : * not an IS NULL-type clause. For success, the clause must enforce
1982 : * *only* nullness of the particular Var, not any other conditions.
1983 : *
1984 : * This is just the single-clause case of find_forced_null_vars(), without
1985 : * any allowance for AND conditions. It's used by initsplan.c on individual
1986 : * qual clauses. The reason for not just applying find_forced_null_vars()
1987 : * is that if an AND of an IS NULL clause with something else were to somehow
1988 : * survive AND/OR flattening, initsplan.c might get fooled into discarding
1989 : * the whole clause when only the IS NULL part of it had been proved redundant.
1990 : */
1991 : Var *
1992 617984 : find_forced_null_var(Node *node)
1993 : {
1994 617984 : if (node == NULL)
1995 0 : return NULL;
1996 617984 : if (IsA(node, NullTest))
1997 : {
1998 : /* check for var IS NULL */
1999 11276 : NullTest *expr = (NullTest *) node;
2000 :
2001 11276 : if (expr->nulltesttype == IS_NULL && !expr->argisrow)
2002 : {
2003 4166 : Var *var = (Var *) expr->arg;
2004 :
2005 4166 : if (var && IsA(var, Var) &&
2006 4022 : var->varlevelsup == 0)
2007 4022 : return var;
2008 : }
2009 : }
2010 606708 : else if (IsA(node, BooleanTest))
2011 : {
2012 : /* var IS UNKNOWN is equivalent to var IS NULL */
2013 612 : BooleanTest *expr = (BooleanTest *) node;
2014 :
2015 612 : if (expr->booltesttype == IS_UNKNOWN)
2016 : {
2017 42 : Var *var = (Var *) expr->arg;
2018 :
2019 42 : if (var && IsA(var, Var) &&
2020 42 : var->varlevelsup == 0)
2021 42 : return var;
2022 : }
2023 : }
2024 613920 : return NULL;
2025 : }
2026 :
2027 : /*
2028 : * Can we treat a ScalarArrayOpExpr as strict?
2029 : *
2030 : * If "falseOK" is true, then a "false" result can be considered strict,
2031 : * else we need to guarantee an actual NULL result for NULL input.
2032 : *
2033 : * "foo op ALL array" is strict if the op is strict *and* we can prove
2034 : * that the array input isn't an empty array. We can check that
2035 : * for the cases of an array constant and an ARRAY[] construct.
2036 : *
2037 : * "foo op ANY array" is strict in the falseOK sense if the op is strict.
2038 : * If not falseOK, the test is the same as for "foo op ALL array".
2039 : */
2040 : static bool
2041 10876 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
2042 : {
2043 : Node *rightop;
2044 :
2045 : /* The contained operator must be strict. */
2046 10876 : set_sa_opfuncid(expr);
2047 10876 : if (!func_strict(expr->opfuncid))
2048 0 : return false;
2049 : /* If ANY and falseOK, that's all we need to check. */
2050 10876 : if (expr->useOr && falseOK)
2051 10712 : return true;
2052 : /* Else, we have to see if the array is provably non-empty. */
2053 : Assert(list_length(expr->args) == 2);
2054 164 : rightop = (Node *) lsecond(expr->args);
2055 164 : if (rightop && IsA(rightop, Const))
2056 0 : {
2057 164 : Datum arraydatum = ((Const *) rightop)->constvalue;
2058 164 : bool arrayisnull = ((Const *) rightop)->constisnull;
2059 : ArrayType *arrayval;
2060 : int nitems;
2061 :
2062 164 : if (arrayisnull)
2063 0 : return false;
2064 164 : arrayval = DatumGetArrayTypeP(arraydatum);
2065 164 : nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
2066 164 : if (nitems > 0)
2067 164 : return true;
2068 : }
2069 0 : else if (rightop && IsA(rightop, ArrayExpr))
2070 : {
2071 0 : ArrayExpr *arrayexpr = (ArrayExpr *) rightop;
2072 :
2073 0 : if (arrayexpr->elements != NIL && !arrayexpr->multidims)
2074 0 : return true;
2075 : }
2076 0 : return false;
2077 : }
2078 :
2079 :
2080 : /*****************************************************************************
2081 : * Check for "pseudo-constant" clauses
2082 : *****************************************************************************/
2083 :
2084 : /*
2085 : * is_pseudo_constant_clause
2086 : * Detect whether an expression is "pseudo constant", ie, it contains no
2087 : * variables of the current query level and no uses of volatile functions.
2088 : * Such an expr is not necessarily a true constant: it can still contain
2089 : * Params and outer-level Vars, not to mention functions whose results
2090 : * may vary from one statement to the next. However, the expr's value
2091 : * will be constant over any one scan of the current query, so it can be
2092 : * used as, eg, an indexscan key. (Actually, the condition for indexscan
2093 : * keys is weaker than this; see is_pseudo_constant_for_index().)
2094 : *
2095 : * CAUTION: this function omits to test for one very important class of
2096 : * not-constant expressions, namely aggregates (Aggrefs). In current usage
2097 : * this is only applied to WHERE clauses and so a check for Aggrefs would be
2098 : * a waste of cycles; but be sure to also check contain_agg_clause() if you
2099 : * want to know about pseudo-constness in other contexts. The same goes
2100 : * for window functions (WindowFuncs).
2101 : */
2102 : bool
2103 5832 : is_pseudo_constant_clause(Node *clause)
2104 : {
2105 : /*
2106 : * We could implement this check in one recursive scan. But since the
2107 : * check for volatile functions is both moderately expensive and unlikely
2108 : * to fail, it seems better to look for Vars first and only check for
2109 : * volatile functions if we find no Vars.
2110 : */
2111 5832 : if (!contain_var_clause(clause) &&
2112 5832 : !contain_volatile_functions(clause))
2113 5832 : return true;
2114 0 : return false;
2115 : }
2116 :
2117 : /*
2118 : * is_pseudo_constant_clause_relids
2119 : * Same as above, except caller already has available the var membership
2120 : * of the expression; this lets us avoid the contain_var_clause() scan.
2121 : */
2122 : bool
2123 460238 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
2124 : {
2125 460238 : if (bms_is_empty(relids) &&
2126 452396 : !contain_volatile_functions(clause))
2127 452396 : return true;
2128 7842 : return false;
2129 : }
2130 :
2131 :
2132 : /*****************************************************************************
2133 : * *
2134 : * General clause-manipulating routines *
2135 : * *
2136 : *****************************************************************************/
2137 :
2138 : /*
2139 : * NumRelids
2140 : * (formerly clause_relids)
2141 : *
2142 : * Returns the number of different base relations referenced in 'clause'.
2143 : */
2144 : int
2145 1782 : NumRelids(PlannerInfo *root, Node *clause)
2146 : {
2147 : int result;
2148 1782 : Relids varnos = pull_varnos(root, clause);
2149 :
2150 1782 : varnos = bms_del_members(varnos, root->outer_join_rels);
2151 1782 : result = bms_num_members(varnos);
2152 1782 : bms_free(varnos);
2153 1782 : return result;
2154 : }
2155 :
2156 : /*
2157 : * CommuteOpExpr: commute a binary operator clause
2158 : *
2159 : * XXX the clause is destructively modified!
2160 : */
2161 : void
2162 20386 : CommuteOpExpr(OpExpr *clause)
2163 : {
2164 : Oid opoid;
2165 : Node *temp;
2166 :
2167 : /* Sanity checks: caller is at fault if these fail */
2168 40772 : if (!is_opclause(clause) ||
2169 20386 : list_length(clause->args) != 2)
2170 0 : elog(ERROR, "cannot commute non-binary-operator clause");
2171 :
2172 20386 : opoid = get_commutator(clause->opno);
2173 :
2174 20386 : if (!OidIsValid(opoid))
2175 0 : elog(ERROR, "could not find commutator for operator %u",
2176 : clause->opno);
2177 :
2178 : /*
2179 : * modify the clause in-place!
2180 : */
2181 20386 : clause->opno = opoid;
2182 20386 : clause->opfuncid = InvalidOid;
2183 : /* opresulttype, opretset, opcollid, inputcollid need not change */
2184 :
2185 20386 : temp = linitial(clause->args);
2186 20386 : linitial(clause->args) = lsecond(clause->args);
2187 20386 : lsecond(clause->args) = temp;
2188 20386 : }
2189 :
2190 : /*
2191 : * Helper for eval_const_expressions: check that datatype of an attribute
2192 : * is still what it was when the expression was parsed. This is needed to
2193 : * guard against improper simplification after ALTER COLUMN TYPE. (XXX we
2194 : * may well need to make similar checks elsewhere?)
2195 : *
2196 : * rowtypeid may come from a whole-row Var, and therefore it can be a domain
2197 : * over composite, but for this purpose we only care about checking the type
2198 : * of a contained field.
2199 : */
2200 : static bool
2201 720 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
2202 : Oid expectedtype, int32 expectedtypmod,
2203 : Oid expectedcollation)
2204 : {
2205 : TupleDesc tupdesc;
2206 : Form_pg_attribute attr;
2207 :
2208 : /* No issue for RECORD, since there is no way to ALTER such a type */
2209 720 : if (rowtypeid == RECORDOID)
2210 56 : return true;
2211 664 : tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
2212 664 : if (fieldnum <= 0 || fieldnum > tupdesc->natts)
2213 : {
2214 0 : ReleaseTupleDesc(tupdesc);
2215 0 : return false;
2216 : }
2217 664 : attr = TupleDescAttr(tupdesc, fieldnum - 1);
2218 664 : if (attr->attisdropped ||
2219 664 : attr->atttypid != expectedtype ||
2220 664 : attr->atttypmod != expectedtypmod ||
2221 664 : attr->attcollation != expectedcollation)
2222 : {
2223 0 : ReleaseTupleDesc(tupdesc);
2224 0 : return false;
2225 : }
2226 664 : ReleaseTupleDesc(tupdesc);
2227 664 : return true;
2228 : }
2229 :
2230 :
2231 : /*--------------------
2232 : * eval_const_expressions
2233 : *
2234 : * Reduce any recognizably constant subexpressions of the given
2235 : * expression tree, for example "2 + 2" => "4". More interestingly,
2236 : * we can reduce certain boolean expressions even when they contain
2237 : * non-constant subexpressions: "x OR true" => "true" no matter what
2238 : * the subexpression x is. (XXX We assume that no such subexpression
2239 : * will have important side-effects, which is not necessarily a good
2240 : * assumption in the presence of user-defined functions; do we need a
2241 : * pg_proc flag that prevents discarding the execution of a function?)
2242 : *
2243 : * We do understand that certain functions may deliver non-constant
2244 : * results even with constant inputs, "nextval()" being the classic
2245 : * example. Functions that are not marked "immutable" in pg_proc
2246 : * will not be pre-evaluated here, although we will reduce their
2247 : * arguments as far as possible.
2248 : *
2249 : * Whenever a function is eliminated from the expression by means of
2250 : * constant-expression evaluation or inlining, we add the function to
2251 : * root->glob->invalItems. This ensures the plan is known to depend on
2252 : * such functions, even though they aren't referenced anymore.
2253 : *
2254 : * We assume that the tree has already been type-checked and contains
2255 : * only operators and functions that are reasonable to try to execute.
2256 : *
2257 : * NOTE: "root" can be passed as NULL if the caller never wants to do any
2258 : * Param substitutions nor receive info about inlined functions nor reduce
2259 : * NullTest for Vars to constant true or constant false.
2260 : *
2261 : * NOTE: the planner assumes that this will always flatten nested AND and
2262 : * OR clauses into N-argument form. See comments in prepqual.c.
2263 : *
2264 : * NOTE: another critical effect is that any function calls that require
2265 : * default arguments will be expanded, and named-argument calls will be
2266 : * converted to positional notation. The executor won't handle either.
2267 : *--------------------
2268 : */
2269 : Node *
2270 1269442 : eval_const_expressions(PlannerInfo *root, Node *node)
2271 : {
2272 : eval_const_expressions_context context;
2273 :
2274 1269442 : if (root)
2275 1016150 : context.boundParams = root->glob->boundParams; /* bound Params */
2276 : else
2277 253292 : context.boundParams = NULL;
2278 1269442 : context.root = root; /* for inlined-function dependencies */
2279 1269442 : context.active_fns = NIL; /* nothing being recursively simplified */
2280 1269442 : context.case_val = NULL; /* no CASE being examined */
2281 1269442 : context.estimate = false; /* safe transformations only */
2282 1269442 : return eval_const_expressions_mutator(node, &context);
2283 : }
2284 :
2285 : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
2286 : /*--------------------
2287 : * convert_saop_to_hashed_saop
2288 : *
2289 : * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
2290 : * function for any ScalarArrayOpExpr that looks like it would be useful to
2291 : * evaluate using a hash table rather than a linear search.
2292 : *
2293 : * We'll use a hash table if all of the following conditions are met:
2294 : * 1. The 2nd argument of the array contain only Consts.
2295 : * 2. useOr is true or there is a valid negator operator for the
2296 : * ScalarArrayOpExpr's opno.
2297 : * 3. There's valid hash function for both left and righthand operands and
2298 : * these hash functions are the same.
2299 : * 4. If the array contains enough elements for us to consider it to be
2300 : * worthwhile using a hash table rather than a linear search.
2301 : */
2302 : void
2303 882620 : convert_saop_to_hashed_saop(Node *node)
2304 : {
2305 882620 : (void) convert_saop_to_hashed_saop_walker(node, NULL);
2306 882620 : }
2307 :
2308 : static bool
2309 6263924 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
2310 : {
2311 6263924 : if (node == NULL)
2312 140252 : return false;
2313 :
2314 6123672 : if (IsA(node, ScalarArrayOpExpr))
2315 : {
2316 33558 : ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
2317 33558 : Expr *arrayarg = (Expr *) lsecond(saop->args);
2318 : Oid lefthashfunc;
2319 : Oid righthashfunc;
2320 :
2321 33558 : if (arrayarg && IsA(arrayarg, Const) &&
2322 18244 : !((Const *) arrayarg)->constisnull)
2323 : {
2324 18214 : if (saop->useOr)
2325 : {
2326 15798 : if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
2327 15464 : lefthashfunc == righthashfunc)
2328 : {
2329 15438 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2330 15438 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2331 : int nitems;
2332 :
2333 : /*
2334 : * Only fill in the hash functions if the array looks
2335 : * large enough for it to be worth hashing instead of
2336 : * doing a linear search.
2337 : */
2338 15438 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2339 :
2340 15438 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2341 : {
2342 : /* Looks good. Fill in the hash functions */
2343 442 : saop->hashfuncid = lefthashfunc;
2344 : }
2345 17684 : return false;
2346 : }
2347 : }
2348 : else /* !saop->useOr */
2349 : {
2350 2416 : Oid negator = get_negator(saop->opno);
2351 :
2352 : /*
2353 : * Check if this is a NOT IN using an operator whose negator
2354 : * is hashable. If so we can still build a hash table and
2355 : * just ensure the lookup items are not in the hash table.
2356 : */
2357 4832 : if (OidIsValid(negator) &&
2358 2416 : get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
2359 2246 : lefthashfunc == righthashfunc)
2360 : {
2361 2246 : Datum arrdatum = ((Const *) arrayarg)->constvalue;
2362 2246 : ArrayType *arr = (ArrayType *) DatumGetPointer(arrdatum);
2363 : int nitems;
2364 :
2365 : /*
2366 : * Only fill in the hash functions if the array looks
2367 : * large enough for it to be worth hashing instead of
2368 : * doing a linear search.
2369 : */
2370 2246 : nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
2371 :
2372 2246 : if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
2373 : {
2374 : /* Looks good. Fill in the hash functions */
2375 70 : saop->hashfuncid = lefthashfunc;
2376 :
2377 : /*
2378 : * Also set the negfuncid. The executor will need
2379 : * that to perform hashtable lookups.
2380 : */
2381 70 : saop->negfuncid = get_opcode(negator);
2382 : }
2383 2246 : return false;
2384 : }
2385 : }
2386 : }
2387 : }
2388 :
2389 6105988 : return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
2390 : }
2391 :
2392 :
2393 : /*--------------------
2394 : * estimate_expression_value
2395 : *
2396 : * This function attempts to estimate the value of an expression for
2397 : * planning purposes. It is in essence a more aggressive version of
2398 : * eval_const_expressions(): we will perform constant reductions that are
2399 : * not necessarily 100% safe, but are reasonable for estimation purposes.
2400 : *
2401 : * Currently the extra steps that are taken in this mode are:
2402 : * 1. Substitute values for Params, where a bound Param value has been made
2403 : * available by the caller of planner(), even if the Param isn't marked
2404 : * constant. This effectively means that we plan using the first supplied
2405 : * value of the Param.
2406 : * 2. Fold stable, as well as immutable, functions to constants.
2407 : * 3. Reduce PlaceHolderVar nodes to their contained expressions.
2408 : *--------------------
2409 : */
2410 : Node *
2411 905484 : estimate_expression_value(PlannerInfo *root, Node *node)
2412 : {
2413 : eval_const_expressions_context context;
2414 :
2415 905484 : context.boundParams = root->glob->boundParams; /* bound Params */
2416 : /* we do not need to mark the plan as depending on inlined functions */
2417 905484 : context.root = NULL;
2418 905484 : context.active_fns = NIL; /* nothing being recursively simplified */
2419 905484 : context.case_val = NULL; /* no CASE being examined */
2420 905484 : context.estimate = true; /* unsafe transformations OK */
2421 905484 : return eval_const_expressions_mutator(node, &context);
2422 : }
2423 :
2424 : /*
2425 : * The generic case in eval_const_expressions_mutator is to recurse using
2426 : * expression_tree_mutator, which will copy the given node unchanged but
2427 : * const-simplify its arguments (if any) as far as possible. If the node
2428 : * itself does immutable processing, and each of its arguments were reduced
2429 : * to a Const, we can then reduce it to a Const using evaluate_expr. (Some
2430 : * node types need more complicated logic; for example, a CASE expression
2431 : * might be reducible to a constant even if not all its subtrees are.)
2432 : */
2433 : #define ece_generic_processing(node) \
2434 : expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
2435 : context)
2436 :
2437 : /*
2438 : * Check whether all arguments of the given node were reduced to Consts.
2439 : * By going directly to expression_tree_walker, contain_non_const_walker
2440 : * is not applied to the node itself, only to its children.
2441 : */
2442 : #define ece_all_arguments_const(node) \
2443 : (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
2444 :
2445 : /* Generic macro for applying evaluate_expr */
2446 : #define ece_evaluate_expr(node) \
2447 : ((Node *) evaluate_expr((Expr *) (node), \
2448 : exprType((Node *) (node)), \
2449 : exprTypmod((Node *) (node)), \
2450 : exprCollation((Node *) (node))))
2451 :
2452 : /*
2453 : * Recursive guts of eval_const_expressions/estimate_expression_value
2454 : */
2455 : static Node *
2456 9375304 : eval_const_expressions_mutator(Node *node,
2457 : eval_const_expressions_context *context)
2458 : {
2459 :
2460 : /* since this function recurses, it could be driven to stack overflow */
2461 9375304 : check_stack_depth();
2462 :
2463 9375304 : if (node == NULL)
2464 407478 : return NULL;
2465 8967826 : switch (nodeTag(node))
2466 : {
2467 150118 : case T_Param:
2468 : {
2469 150118 : Param *param = (Param *) node;
2470 150118 : ParamListInfo paramLI = context->boundParams;
2471 :
2472 : /* Look to see if we've been given a value for this Param */
2473 150118 : if (param->paramkind == PARAM_EXTERN &&
2474 53590 : paramLI != NULL &&
2475 53590 : param->paramid > 0 &&
2476 53590 : param->paramid <= paramLI->numParams)
2477 : {
2478 : ParamExternData *prm;
2479 : ParamExternData prmdata;
2480 :
2481 : /*
2482 : * Give hook a chance in case parameter is dynamic. Tell
2483 : * it that this fetch is speculative, so it should avoid
2484 : * erroring out if parameter is unavailable.
2485 : */
2486 53590 : if (paramLI->paramFetch != NULL)
2487 7452 : prm = paramLI->paramFetch(paramLI, param->paramid,
2488 : true, &prmdata);
2489 : else
2490 46138 : prm = ¶mLI->params[param->paramid - 1];
2491 :
2492 : /*
2493 : * We don't just check OidIsValid, but insist that the
2494 : * fetched type match the Param, just in case the hook did
2495 : * something unexpected. No need to throw an error here
2496 : * though; leave that for runtime.
2497 : */
2498 53590 : if (OidIsValid(prm->ptype) &&
2499 53590 : prm->ptype == param->paramtype)
2500 : {
2501 : /* OK to substitute parameter value? */
2502 53588 : if (context->estimate ||
2503 53588 : (prm->pflags & PARAM_FLAG_CONST))
2504 : {
2505 : /*
2506 : * Return a Const representing the param value.
2507 : * Must copy pass-by-ref datatypes, since the
2508 : * Param might be in a memory context
2509 : * shorter-lived than our output plan should be.
2510 : */
2511 : int16 typLen;
2512 : bool typByVal;
2513 : Datum pval;
2514 : Const *con;
2515 :
2516 53588 : get_typlenbyval(param->paramtype,
2517 : &typLen, &typByVal);
2518 53588 : if (prm->isnull || typByVal)
2519 35354 : pval = prm->value;
2520 : else
2521 18234 : pval = datumCopy(prm->value, typByVal, typLen);
2522 53588 : con = makeConst(param->paramtype,
2523 : param->paramtypmod,
2524 : param->paramcollid,
2525 : (int) typLen,
2526 : pval,
2527 53588 : prm->isnull,
2528 : typByVal);
2529 53588 : con->location = param->location;
2530 53588 : return (Node *) con;
2531 : }
2532 : }
2533 : }
2534 :
2535 : /*
2536 : * Not replaceable, so just copy the Param (no need to
2537 : * recurse)
2538 : */
2539 96530 : return (Node *) copyObject(param);
2540 : }
2541 3608 : case T_WindowFunc:
2542 : {
2543 3608 : WindowFunc *expr = (WindowFunc *) node;
2544 3608 : Oid funcid = expr->winfnoid;
2545 : List *args;
2546 : Expr *aggfilter;
2547 : HeapTuple func_tuple;
2548 : WindowFunc *newexpr;
2549 :
2550 : /*
2551 : * We can't really simplify a WindowFunc node, but we mustn't
2552 : * just fall through to the default processing, because we
2553 : * have to apply expand_function_arguments to its argument
2554 : * list. That takes care of inserting default arguments and
2555 : * expanding named-argument notation.
2556 : */
2557 3608 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
2558 3608 : if (!HeapTupleIsValid(func_tuple))
2559 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
2560 :
2561 3608 : args = expand_function_arguments(expr->args,
2562 : false, expr->wintype,
2563 : func_tuple);
2564 :
2565 3608 : ReleaseSysCache(func_tuple);
2566 :
2567 : /* Now, recursively simplify the args (which are a List) */
2568 : args = (List *)
2569 3608 : expression_tree_mutator((Node *) args,
2570 : eval_const_expressions_mutator,
2571 : context);
2572 : /* ... and the filter expression, which isn't */
2573 : aggfilter = (Expr *)
2574 3608 : eval_const_expressions_mutator((Node *) expr->aggfilter,
2575 : context);
2576 :
2577 : /* And build the replacement WindowFunc node */
2578 3608 : newexpr = makeNode(WindowFunc);
2579 3608 : newexpr->winfnoid = expr->winfnoid;
2580 3608 : newexpr->wintype = expr->wintype;
2581 3608 : newexpr->wincollid = expr->wincollid;
2582 3608 : newexpr->inputcollid = expr->inputcollid;
2583 3608 : newexpr->args = args;
2584 3608 : newexpr->aggfilter = aggfilter;
2585 3608 : newexpr->runCondition = expr->runCondition;
2586 3608 : newexpr->winref = expr->winref;
2587 3608 : newexpr->winstar = expr->winstar;
2588 3608 : newexpr->winagg = expr->winagg;
2589 3608 : newexpr->ignore_nulls = expr->ignore_nulls;
2590 3608 : newexpr->location = expr->location;
2591 :
2592 3608 : return (Node *) newexpr;
2593 : }
2594 551424 : case T_FuncExpr:
2595 : {
2596 551424 : FuncExpr *expr = (FuncExpr *) node;
2597 551424 : List *args = expr->args;
2598 : Expr *simple;
2599 : FuncExpr *newexpr;
2600 :
2601 : /*
2602 : * Code for op/func reduction is pretty bulky, so split it out
2603 : * as a separate function. Note: exprTypmod normally returns
2604 : * -1 for a FuncExpr, but not when the node is recognizably a
2605 : * length coercion; we want to preserve the typmod in the
2606 : * eventual Const if so.
2607 : */
2608 551424 : simple = simplify_function(expr->funcid,
2609 : expr->funcresulttype,
2610 : exprTypmod(node),
2611 : expr->funccollid,
2612 : expr->inputcollid,
2613 : &args,
2614 551424 : expr->funcvariadic,
2615 : true,
2616 : true,
2617 : context);
2618 548632 : if (simple) /* successfully simplified it */
2619 159152 : return (Node *) simple;
2620 :
2621 : /*
2622 : * The expression cannot be simplified any further, so build
2623 : * and return a replacement FuncExpr node using the
2624 : * possibly-simplified arguments. Note that we have also
2625 : * converted the argument list to positional notation.
2626 : */
2627 389480 : newexpr = makeNode(FuncExpr);
2628 389480 : newexpr->funcid = expr->funcid;
2629 389480 : newexpr->funcresulttype = expr->funcresulttype;
2630 389480 : newexpr->funcretset = expr->funcretset;
2631 389480 : newexpr->funcvariadic = expr->funcvariadic;
2632 389480 : newexpr->funcformat = expr->funcformat;
2633 389480 : newexpr->funccollid = expr->funccollid;
2634 389480 : newexpr->inputcollid = expr->inputcollid;
2635 389480 : newexpr->args = args;
2636 389480 : newexpr->location = expr->location;
2637 389480 : return (Node *) newexpr;
2638 : }
2639 50714 : case T_Aggref:
2640 50714 : node = ece_generic_processing(node);
2641 50714 : if (context->root != NULL)
2642 50714 : return simplify_aggref((Aggref *) node, context);
2643 0 : return node;
2644 710756 : case T_OpExpr:
2645 : {
2646 710756 : OpExpr *expr = (OpExpr *) node;
2647 710756 : List *args = expr->args;
2648 : Expr *simple;
2649 : OpExpr *newexpr;
2650 :
2651 : /*
2652 : * Need to get OID of underlying function. Okay to scribble
2653 : * on input to this extent.
2654 : */
2655 710756 : set_opfuncid(expr);
2656 :
2657 : /*
2658 : * Code for op/func reduction is pretty bulky, so split it out
2659 : * as a separate function.
2660 : */
2661 710756 : simple = simplify_function(expr->opfuncid,
2662 : expr->opresulttype, -1,
2663 : expr->opcollid,
2664 : expr->inputcollid,
2665 : &args,
2666 : false,
2667 : true,
2668 : true,
2669 : context);
2670 709574 : if (simple) /* successfully simplified it */
2671 23126 : return (Node *) simple;
2672 :
2673 : /*
2674 : * If the operator is boolean equality or inequality, we know
2675 : * how to simplify cases involving one constant and one
2676 : * non-constant argument.
2677 : */
2678 686448 : if (expr->opno == BooleanEqualOperator ||
2679 685254 : expr->opno == BooleanNotEqualOperator)
2680 : {
2681 1362 : simple = (Expr *) simplify_boolean_equality(expr->opno,
2682 : args);
2683 1362 : if (simple) /* successfully simplified it */
2684 1094 : return (Node *) simple;
2685 : }
2686 :
2687 : /*
2688 : * The expression cannot be simplified any further, so build
2689 : * and return a replacement OpExpr node using the
2690 : * possibly-simplified arguments.
2691 : */
2692 685354 : newexpr = makeNode(OpExpr);
2693 685354 : newexpr->opno = expr->opno;
2694 685354 : newexpr->opfuncid = expr->opfuncid;
2695 685354 : newexpr->opresulttype = expr->opresulttype;
2696 685354 : newexpr->opretset = expr->opretset;
2697 685354 : newexpr->opcollid = expr->opcollid;
2698 685354 : newexpr->inputcollid = expr->inputcollid;
2699 685354 : newexpr->args = args;
2700 685354 : newexpr->location = expr->location;
2701 685354 : return (Node *) newexpr;
2702 : }
2703 1238 : case T_DistinctExpr:
2704 : {
2705 1238 : DistinctExpr *expr = (DistinctExpr *) node;
2706 : List *args;
2707 : ListCell *arg;
2708 1238 : bool has_null_input = false;
2709 1238 : bool all_null_input = true;
2710 1238 : bool has_nonconst_input = false;
2711 : Expr *simple;
2712 : DistinctExpr *newexpr;
2713 :
2714 : /*
2715 : * Reduce constants in the DistinctExpr's arguments. We know
2716 : * args is either NIL or a List node, so we can call
2717 : * expression_tree_mutator directly rather than recursing to
2718 : * self.
2719 : */
2720 1238 : args = (List *) expression_tree_mutator((Node *) expr->args,
2721 : eval_const_expressions_mutator,
2722 : context);
2723 :
2724 : /*
2725 : * We must do our own check for NULLs because DistinctExpr has
2726 : * different results for NULL input than the underlying
2727 : * operator does.
2728 : */
2729 3714 : foreach(arg, args)
2730 : {
2731 2476 : if (IsA(lfirst(arg), Const))
2732 : {
2733 370 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
2734 370 : all_null_input &= ((Const *) lfirst(arg))->constisnull;
2735 : }
2736 : else
2737 2106 : has_nonconst_input = true;
2738 : }
2739 :
2740 : /* all constants? then can optimize this out */
2741 1238 : if (!has_nonconst_input)
2742 : {
2743 : /* all nulls? then not distinct */
2744 54 : if (all_null_input)
2745 12 : return makeBoolConst(false, false);
2746 :
2747 : /* one null? then distinct */
2748 42 : if (has_null_input)
2749 18 : return makeBoolConst(true, false);
2750 :
2751 : /* otherwise try to evaluate the '=' operator */
2752 : /* (NOT okay to try to inline it, though!) */
2753 :
2754 : /*
2755 : * Need to get OID of underlying function. Okay to
2756 : * scribble on input to this extent.
2757 : */
2758 24 : set_opfuncid((OpExpr *) expr); /* rely on struct
2759 : * equivalence */
2760 :
2761 : /*
2762 : * Code for op/func reduction is pretty bulky, so split it
2763 : * out as a separate function.
2764 : */
2765 24 : simple = simplify_function(expr->opfuncid,
2766 : expr->opresulttype, -1,
2767 : expr->opcollid,
2768 : expr->inputcollid,
2769 : &args,
2770 : false,
2771 : false,
2772 : false,
2773 : context);
2774 24 : if (simple) /* successfully simplified it */
2775 : {
2776 : /*
2777 : * Since the underlying operator is "=", must negate
2778 : * its result
2779 : */
2780 24 : Const *csimple = castNode(Const, simple);
2781 :
2782 24 : csimple->constvalue =
2783 24 : BoolGetDatum(!DatumGetBool(csimple->constvalue));
2784 24 : return (Node *) csimple;
2785 : }
2786 : }
2787 :
2788 : /*
2789 : * The expression cannot be simplified any further, so build
2790 : * and return a replacement DistinctExpr node using the
2791 : * possibly-simplified arguments.
2792 : */
2793 1184 : newexpr = makeNode(DistinctExpr);
2794 1184 : newexpr->opno = expr->opno;
2795 1184 : newexpr->opfuncid = expr->opfuncid;
2796 1184 : newexpr->opresulttype = expr->opresulttype;
2797 1184 : newexpr->opretset = expr->opretset;
2798 1184 : newexpr->opcollid = expr->opcollid;
2799 1184 : newexpr->inputcollid = expr->inputcollid;
2800 1184 : newexpr->args = args;
2801 1184 : newexpr->location = expr->location;
2802 1184 : return (Node *) newexpr;
2803 : }
2804 740 : case T_NullIfExpr:
2805 : {
2806 : NullIfExpr *expr;
2807 : ListCell *arg;
2808 740 : bool has_nonconst_input = false;
2809 :
2810 : /* Copy the node and const-simplify its arguments */
2811 740 : expr = (NullIfExpr *) ece_generic_processing(node);
2812 :
2813 : /* If either argument is NULL they can't be equal */
2814 2214 : foreach(arg, expr->args)
2815 : {
2816 1480 : if (!IsA(lfirst(arg), Const))
2817 708 : has_nonconst_input = true;
2818 772 : else if (((Const *) lfirst(arg))->constisnull)
2819 6 : return (Node *) linitial(expr->args);
2820 : }
2821 :
2822 : /*
2823 : * Need to get OID of underlying function before checking if
2824 : * the function is OK to evaluate.
2825 : */
2826 734 : set_opfuncid((OpExpr *) expr);
2827 :
2828 772 : if (!has_nonconst_input &&
2829 38 : ece_function_is_safe(expr->opfuncid, context))
2830 38 : return ece_evaluate_expr(expr);
2831 :
2832 696 : return (Node *) expr;
2833 : }
2834 38594 : case T_ScalarArrayOpExpr:
2835 : {
2836 : ScalarArrayOpExpr *saop;
2837 :
2838 : /* Copy the node and const-simplify its arguments */
2839 38594 : saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
2840 :
2841 : /* Make sure we know underlying function */
2842 38594 : set_sa_opfuncid(saop);
2843 :
2844 : /*
2845 : * If all arguments are Consts, and it's a safe function, we
2846 : * can fold to a constant
2847 : */
2848 38932 : if (ece_all_arguments_const(saop) &&
2849 338 : ece_function_is_safe(saop->opfuncid, context))
2850 338 : return ece_evaluate_expr(saop);
2851 38256 : return (Node *) saop;
2852 : }
2853 172906 : case T_BoolExpr:
2854 : {
2855 172906 : BoolExpr *expr = (BoolExpr *) node;
2856 :
2857 172906 : switch (expr->boolop)
2858 : {
2859 12836 : case OR_EXPR:
2860 : {
2861 : List *newargs;
2862 12836 : bool haveNull = false;
2863 12836 : bool forceTrue = false;
2864 :
2865 12836 : newargs = simplify_or_arguments(expr->args,
2866 : context,
2867 : &haveNull,
2868 : &forceTrue);
2869 12836 : if (forceTrue)
2870 172 : return makeBoolConst(true, false);
2871 12664 : if (haveNull)
2872 30 : newargs = lappend(newargs,
2873 30 : makeBoolConst(false, true));
2874 : /* If all the inputs are FALSE, result is FALSE */
2875 12664 : if (newargs == NIL)
2876 34 : return makeBoolConst(false, false);
2877 :
2878 : /*
2879 : * If only one nonconst-or-NULL input, it's the
2880 : * result
2881 : */
2882 12630 : if (list_length(newargs) == 1)
2883 138 : return (Node *) linitial(newargs);
2884 : /* Else we still need an OR node */
2885 12492 : return (Node *) make_orclause(newargs);
2886 : }
2887 145182 : case AND_EXPR:
2888 : {
2889 : List *newargs;
2890 145182 : bool haveNull = false;
2891 145182 : bool forceFalse = false;
2892 :
2893 145182 : newargs = simplify_and_arguments(expr->args,
2894 : context,
2895 : &haveNull,
2896 : &forceFalse);
2897 145182 : if (forceFalse)
2898 1554 : return makeBoolConst(false, false);
2899 143628 : if (haveNull)
2900 6 : newargs = lappend(newargs,
2901 6 : makeBoolConst(false, true));
2902 : /* If all the inputs are TRUE, result is TRUE */
2903 143628 : if (newargs == NIL)
2904 394 : return makeBoolConst(true, false);
2905 :
2906 : /*
2907 : * If only one nonconst-or-NULL input, it's the
2908 : * result
2909 : */
2910 143234 : if (list_length(newargs) == 1)
2911 196 : return (Node *) linitial(newargs);
2912 : /* Else we still need an AND node */
2913 143038 : return (Node *) make_andclause(newargs);
2914 : }
2915 14888 : case NOT_EXPR:
2916 : {
2917 : Node *arg;
2918 :
2919 : Assert(list_length(expr->args) == 1);
2920 14888 : arg = eval_const_expressions_mutator(linitial(expr->args),
2921 : context);
2922 :
2923 : /*
2924 : * Use negate_clause() to see if we can simplify
2925 : * away the NOT.
2926 : */
2927 14888 : return negate_clause(arg);
2928 : }
2929 0 : default:
2930 0 : elog(ERROR, "unrecognized boolop: %d",
2931 : (int) expr->boolop);
2932 : break;
2933 : }
2934 : break;
2935 : }
2936 :
2937 774 : case T_JsonValueExpr:
2938 : {
2939 774 : JsonValueExpr *jve = (JsonValueExpr *) node;
2940 774 : Node *raw_expr = (Node *) jve->raw_expr;
2941 774 : Node *formatted_expr = (Node *) jve->formatted_expr;
2942 :
2943 : /*
2944 : * If we can fold formatted_expr to a constant, we can elide
2945 : * the JsonValueExpr altogether. Otherwise we must process
2946 : * raw_expr too. But JsonFormat is a flat node and requires
2947 : * no simplification, only copying.
2948 : */
2949 774 : formatted_expr = eval_const_expressions_mutator(formatted_expr,
2950 : context);
2951 774 : if (formatted_expr && IsA(formatted_expr, Const))
2952 546 : return formatted_expr;
2953 :
2954 228 : raw_expr = eval_const_expressions_mutator(raw_expr, context);
2955 :
2956 228 : return (Node *) makeJsonValueExpr((Expr *) raw_expr,
2957 : (Expr *) formatted_expr,
2958 228 : copyObject(jve->format));
2959 : }
2960 :
2961 582 : case T_SubPlan:
2962 : case T_AlternativeSubPlan:
2963 :
2964 : /*
2965 : * Return a SubPlan unchanged --- too late to do anything with it.
2966 : *
2967 : * XXX should we ereport() here instead? Probably this routine
2968 : * should never be invoked after SubPlan creation.
2969 : */
2970 582 : return node;
2971 175544 : case T_RelabelType:
2972 : {
2973 175544 : RelabelType *relabel = (RelabelType *) node;
2974 : Node *arg;
2975 :
2976 : /* Simplify the input ... */
2977 175544 : arg = eval_const_expressions_mutator((Node *) relabel->arg,
2978 : context);
2979 : /* ... and attach a new RelabelType node, if needed */
2980 175538 : return applyRelabelType(arg,
2981 : relabel->resulttype,
2982 : relabel->resulttypmod,
2983 : relabel->resultcollid,
2984 : relabel->relabelformat,
2985 : relabel->location,
2986 : true);
2987 : }
2988 26630 : case T_CoerceViaIO:
2989 : {
2990 26630 : CoerceViaIO *expr = (CoerceViaIO *) node;
2991 : List *args;
2992 : Oid outfunc;
2993 : bool outtypisvarlena;
2994 : Oid infunc;
2995 : Oid intypioparam;
2996 : Expr *simple;
2997 : CoerceViaIO *newexpr;
2998 :
2999 : /* Make a List so we can use simplify_function */
3000 26630 : args = list_make1(expr->arg);
3001 :
3002 : /*
3003 : * CoerceViaIO represents calling the source type's output
3004 : * function then the result type's input function. So, try to
3005 : * simplify it as though it were a stack of two such function
3006 : * calls. First we need to know what the functions are.
3007 : *
3008 : * Note that the coercion functions are assumed not to care
3009 : * about input collation, so we just pass InvalidOid for that.
3010 : */
3011 26630 : getTypeOutputInfo(exprType((Node *) expr->arg),
3012 : &outfunc, &outtypisvarlena);
3013 26630 : getTypeInputInfo(expr->resulttype,
3014 : &infunc, &intypioparam);
3015 :
3016 26630 : simple = simplify_function(outfunc,
3017 : CSTRINGOID, -1,
3018 : InvalidOid,
3019 : InvalidOid,
3020 : &args,
3021 : false,
3022 : true,
3023 : true,
3024 : context);
3025 26630 : if (simple) /* successfully simplified output fn */
3026 : {
3027 : /*
3028 : * Input functions may want 1 to 3 arguments. We always
3029 : * supply all three, trusting that nothing downstream will
3030 : * complain.
3031 : */
3032 2488 : args = list_make3(simple,
3033 : makeConst(OIDOID,
3034 : -1,
3035 : InvalidOid,
3036 : sizeof(Oid),
3037 : ObjectIdGetDatum(intypioparam),
3038 : false,
3039 : true),
3040 : makeConst(INT4OID,
3041 : -1,
3042 : InvalidOid,
3043 : sizeof(int32),
3044 : Int32GetDatum(-1),
3045 : false,
3046 : true));
3047 :
3048 2488 : simple = simplify_function(infunc,
3049 : expr->resulttype, -1,
3050 : expr->resultcollid,
3051 : InvalidOid,
3052 : &args,
3053 : false,
3054 : false,
3055 : true,
3056 : context);
3057 2382 : if (simple) /* successfully simplified input fn */
3058 2302 : return (Node *) simple;
3059 : }
3060 :
3061 : /*
3062 : * The expression cannot be simplified any further, so build
3063 : * and return a replacement CoerceViaIO node using the
3064 : * possibly-simplified argument.
3065 : */
3066 24222 : newexpr = makeNode(CoerceViaIO);
3067 24222 : newexpr->arg = (Expr *) linitial(args);
3068 24222 : newexpr->resulttype = expr->resulttype;
3069 24222 : newexpr->resultcollid = expr->resultcollid;
3070 24222 : newexpr->coerceformat = expr->coerceformat;
3071 24222 : newexpr->location = expr->location;
3072 24222 : return (Node *) newexpr;
3073 : }
3074 10206 : case T_ArrayCoerceExpr:
3075 : {
3076 10206 : ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
3077 : Node *save_case_val;
3078 :
3079 : /*
3080 : * Copy the node and const-simplify its arguments. We can't
3081 : * use ece_generic_processing() here because we need to mess
3082 : * with case_val only while processing the elemexpr.
3083 : */
3084 10206 : memcpy(ac, node, sizeof(ArrayCoerceExpr));
3085 10206 : ac->arg = (Expr *)
3086 10206 : eval_const_expressions_mutator((Node *) ac->arg,
3087 : context);
3088 :
3089 : /*
3090 : * Set up for the CaseTestExpr node contained in the elemexpr.
3091 : * We must prevent it from absorbing any outer CASE value.
3092 : */
3093 10206 : save_case_val = context->case_val;
3094 10206 : context->case_val = NULL;
3095 :
3096 10206 : ac->elemexpr = (Expr *)
3097 10206 : eval_const_expressions_mutator((Node *) ac->elemexpr,
3098 : context);
3099 :
3100 10206 : context->case_val = save_case_val;
3101 :
3102 : /*
3103 : * If constant argument and the per-element expression is
3104 : * immutable, we can simplify the whole thing to a constant.
3105 : * Exception: although contain_mutable_functions considers
3106 : * CoerceToDomain immutable for historical reasons, let's not
3107 : * do so here; this ensures coercion to an array-over-domain
3108 : * does not apply the domain's constraints until runtime.
3109 : */
3110 10206 : if (ac->arg && IsA(ac->arg, Const) &&
3111 1168 : ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
3112 1144 : !contain_mutable_functions((Node *) ac->elemexpr))
3113 1144 : return ece_evaluate_expr(ac);
3114 :
3115 9062 : return (Node *) ac;
3116 : }
3117 9486 : case T_CollateExpr:
3118 : {
3119 : /*
3120 : * We replace CollateExpr with RelabelType, so as to improve
3121 : * uniformity of expression representation and thus simplify
3122 : * comparison of expressions. Hence this looks very nearly
3123 : * the same as the RelabelType case, and we can apply the same
3124 : * optimizations to avoid unnecessary RelabelTypes.
3125 : */
3126 9486 : CollateExpr *collate = (CollateExpr *) node;
3127 : Node *arg;
3128 :
3129 : /* Simplify the input ... */
3130 9486 : arg = eval_const_expressions_mutator((Node *) collate->arg,
3131 : context);
3132 : /* ... and attach a new RelabelType node, if needed */
3133 9486 : return applyRelabelType(arg,
3134 : exprType(arg),
3135 : exprTypmod(arg),
3136 : collate->collOid,
3137 : COERCE_IMPLICIT_CAST,
3138 : collate->location,
3139 : true);
3140 : }
3141 33578 : case T_CaseExpr:
3142 : {
3143 : /*----------
3144 : * CASE expressions can be simplified if there are constant
3145 : * condition clauses:
3146 : * FALSE (or NULL): drop the alternative
3147 : * TRUE: drop all remaining alternatives
3148 : * If the first non-FALSE alternative is a constant TRUE,
3149 : * we can simplify the entire CASE to that alternative's
3150 : * expression. If there are no non-FALSE alternatives,
3151 : * we simplify the entire CASE to the default result (ELSE).
3152 : *
3153 : * If we have a simple-form CASE with constant test
3154 : * expression, we substitute the constant value for contained
3155 : * CaseTestExpr placeholder nodes, so that we have the
3156 : * opportunity to reduce constant test conditions. For
3157 : * example this allows
3158 : * CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
3159 : * to reduce to 1 rather than drawing a divide-by-0 error.
3160 : * Note that when the test expression is constant, we don't
3161 : * have to include it in the resulting CASE; for example
3162 : * CASE 0 WHEN x THEN y ELSE z END
3163 : * is transformed by the parser to
3164 : * CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
3165 : * which we can simplify to
3166 : * CASE WHEN 0 = x THEN y ELSE z END
3167 : * It is not necessary for the executor to evaluate the "arg"
3168 : * expression when executing the CASE, since any contained
3169 : * CaseTestExprs that might have referred to it will have been
3170 : * replaced by the constant.
3171 : *----------
3172 : */
3173 33578 : CaseExpr *caseexpr = (CaseExpr *) node;
3174 : CaseExpr *newcase;
3175 : Node *save_case_val;
3176 : Node *newarg;
3177 : List *newargs;
3178 : bool const_true_cond;
3179 33578 : Node *defresult = NULL;
3180 : ListCell *arg;
3181 :
3182 : /* Simplify the test expression, if any */
3183 33578 : newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
3184 : context);
3185 :
3186 : /* Set up for contained CaseTestExpr nodes */
3187 33578 : save_case_val = context->case_val;
3188 33578 : if (newarg && IsA(newarg, Const))
3189 : {
3190 78 : context->case_val = newarg;
3191 78 : newarg = NULL; /* not needed anymore, see above */
3192 : }
3193 : else
3194 33500 : context->case_val = NULL;
3195 :
3196 : /* Simplify the WHEN clauses */
3197 33578 : newargs = NIL;
3198 33578 : const_true_cond = false;
3199 95690 : foreach(arg, caseexpr->args)
3200 : {
3201 62834 : CaseWhen *oldcasewhen = lfirst_node(CaseWhen, arg);
3202 : Node *casecond;
3203 : Node *caseresult;
3204 :
3205 : /* Simplify this alternative's test condition */
3206 62834 : casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
3207 : context);
3208 :
3209 : /*
3210 : * If the test condition is constant FALSE (or NULL), then
3211 : * drop this WHEN clause completely, without processing
3212 : * the result.
3213 : */
3214 62834 : if (casecond && IsA(casecond, Const))
3215 : {
3216 1906 : Const *const_input = (Const *) casecond;
3217 :
3218 1906 : if (const_input->constisnull ||
3219 1906 : !DatumGetBool(const_input->constvalue))
3220 1190 : continue; /* drop alternative with FALSE cond */
3221 : /* Else it's constant TRUE */
3222 716 : const_true_cond = true;
3223 : }
3224 :
3225 : /* Simplify this alternative's result value */
3226 61644 : caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
3227 : context);
3228 :
3229 : /* If non-constant test condition, emit a new WHEN node */
3230 61638 : if (!const_true_cond)
3231 60922 : {
3232 60922 : CaseWhen *newcasewhen = makeNode(CaseWhen);
3233 :
3234 60922 : newcasewhen->expr = (Expr *) casecond;
3235 60922 : newcasewhen->result = (Expr *) caseresult;
3236 60922 : newcasewhen->location = oldcasewhen->location;
3237 60922 : newargs = lappend(newargs, newcasewhen);
3238 60922 : continue;
3239 : }
3240 :
3241 : /*
3242 : * Found a TRUE condition, so none of the remaining
3243 : * alternatives can be reached. We treat the result as
3244 : * the default result.
3245 : */
3246 716 : defresult = caseresult;
3247 716 : break;
3248 : }
3249 :
3250 : /* Simplify the default result, unless we replaced it above */
3251 33572 : if (!const_true_cond)
3252 32856 : defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
3253 : context);
3254 :
3255 33572 : context->case_val = save_case_val;
3256 :
3257 : /*
3258 : * If no non-FALSE alternatives, CASE reduces to the default
3259 : * result
3260 : */
3261 33572 : if (newargs == NIL)
3262 1148 : return defresult;
3263 : /* Otherwise we need a new CASE node */
3264 32424 : newcase = makeNode(CaseExpr);
3265 32424 : newcase->casetype = caseexpr->casetype;
3266 32424 : newcase->casecollid = caseexpr->casecollid;
3267 32424 : newcase->arg = (Expr *) newarg;
3268 32424 : newcase->args = newargs;
3269 32424 : newcase->defresult = (Expr *) defresult;
3270 32424 : newcase->location = caseexpr->location;
3271 32424 : return (Node *) newcase;
3272 : }
3273 33370 : case T_CaseTestExpr:
3274 : {
3275 : /*
3276 : * If we know a constant test value for the current CASE
3277 : * construct, substitute it for the placeholder. Else just
3278 : * return the placeholder as-is.
3279 : */
3280 33370 : if (context->case_val)
3281 128 : return copyObject(context->case_val);
3282 : else
3283 33242 : return copyObject(node);
3284 : }
3285 61062 : case T_SubscriptingRef:
3286 : case T_ArrayExpr:
3287 : case T_RowExpr:
3288 : case T_MinMaxExpr:
3289 : {
3290 : /*
3291 : * Generic handling for node types whose own processing is
3292 : * known to be immutable, and for which we need no smarts
3293 : * beyond "simplify if all inputs are constants".
3294 : *
3295 : * Treating SubscriptingRef this way assumes that subscripting
3296 : * fetch and assignment are both immutable. This constrains
3297 : * type-specific subscripting implementations; maybe we should
3298 : * relax it someday.
3299 : *
3300 : * Treating MinMaxExpr this way amounts to assuming that the
3301 : * btree comparison function it calls is immutable; see the
3302 : * reasoning in contain_mutable_functions_walker.
3303 : */
3304 :
3305 : /* Copy the node and const-simplify its arguments */
3306 61062 : node = ece_generic_processing(node);
3307 : /* If all arguments are Consts, we can fold to a constant */
3308 61062 : if (ece_all_arguments_const(node))
3309 30544 : return ece_evaluate_expr(node);
3310 30518 : return node;
3311 : }
3312 2712 : case T_CoalesceExpr:
3313 : {
3314 2712 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
3315 : CoalesceExpr *newcoalesce;
3316 : List *newargs;
3317 : ListCell *arg;
3318 :
3319 2712 : newargs = NIL;
3320 6408 : foreach(arg, coalesceexpr->args)
3321 : {
3322 : Node *e;
3323 :
3324 5316 : e = eval_const_expressions_mutator((Node *) lfirst(arg),
3325 : context);
3326 :
3327 : /*
3328 : * We can remove null constants from the list. For a
3329 : * nonnullable expression, if it has not been preceded by
3330 : * any non-null-constant expressions then it is the
3331 : * result. Otherwise, it's the next argument, but we can
3332 : * drop following arguments since they will never be
3333 : * reached.
3334 : */
3335 5316 : if (IsA(e, Const))
3336 : {
3337 1592 : if (((Const *) e)->constisnull)
3338 56 : continue; /* drop null constant */
3339 1536 : if (newargs == NIL)
3340 158 : return e; /* first expr */
3341 1438 : newargs = lappend(newargs, e);
3342 1438 : break;
3343 : }
3344 3724 : if (expr_is_nonnullable(context->root, (Expr *) e, false))
3345 : {
3346 84 : if (newargs == NIL)
3347 60 : return e; /* first expr */
3348 24 : newargs = lappend(newargs, e);
3349 24 : break;
3350 : }
3351 :
3352 3640 : newargs = lappend(newargs, e);
3353 : }
3354 :
3355 : /*
3356 : * If all the arguments were constant null, the result is just
3357 : * null
3358 : */
3359 2554 : if (newargs == NIL)
3360 0 : return (Node *) makeNullConst(coalesceexpr->coalescetype,
3361 : -1,
3362 : coalesceexpr->coalescecollid);
3363 :
3364 : /*
3365 : * If there's exactly one surviving argument, we no longer
3366 : * need COALESCE at all: the result is that argument
3367 : */
3368 2554 : if (list_length(newargs) == 1)
3369 18 : return (Node *) linitial(newargs);
3370 :
3371 2536 : newcoalesce = makeNode(CoalesceExpr);
3372 2536 : newcoalesce->coalescetype = coalesceexpr->coalescetype;
3373 2536 : newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
3374 2536 : newcoalesce->args = newargs;
3375 2536 : newcoalesce->location = coalesceexpr->location;
3376 2536 : return (Node *) newcoalesce;
3377 : }
3378 4970 : case T_SQLValueFunction:
3379 : {
3380 : /*
3381 : * All variants of SQLValueFunction are stable, so if we are
3382 : * estimating the expression's value, we should evaluate the
3383 : * current function value. Otherwise just copy.
3384 : */
3385 4970 : SQLValueFunction *svf = (SQLValueFunction *) node;
3386 :
3387 4970 : if (context->estimate)
3388 856 : return (Node *) evaluate_expr((Expr *) svf,
3389 : svf->type,
3390 : svf->typmod,
3391 : InvalidOid);
3392 : else
3393 4114 : return copyObject((Node *) svf);
3394 : }
3395 5662 : case T_FieldSelect:
3396 : {
3397 : /*
3398 : * We can optimize field selection from a whole-row Var into a
3399 : * simple Var. (This case won't be generated directly by the
3400 : * parser, because ParseComplexProjection short-circuits it.
3401 : * But it can arise while simplifying functions.) Also, we
3402 : * can optimize field selection from a RowExpr construct, or
3403 : * of course from a constant.
3404 : *
3405 : * However, replacing a whole-row Var in this way has a
3406 : * pitfall: if we've already built the rel targetlist for the
3407 : * source relation, then the whole-row Var is scheduled to be
3408 : * produced by the relation scan, but the simple Var probably
3409 : * isn't, which will lead to a failure in setrefs.c. This is
3410 : * not a problem when handling simple single-level queries, in
3411 : * which expression simplification always happens first. It
3412 : * is a risk for lateral references from subqueries, though.
3413 : * To avoid such failures, don't optimize uplevel references.
3414 : *
3415 : * We must also check that the declared type of the field is
3416 : * still the same as when the FieldSelect was created --- this
3417 : * can change if someone did ALTER COLUMN TYPE on the rowtype.
3418 : * If it isn't, we skip the optimization; the case will
3419 : * probably fail at runtime, but that's not our problem here.
3420 : */
3421 5662 : FieldSelect *fselect = (FieldSelect *) node;
3422 : FieldSelect *newfselect;
3423 : Node *arg;
3424 :
3425 5662 : arg = eval_const_expressions_mutator((Node *) fselect->arg,
3426 : context);
3427 5662 : if (arg && IsA(arg, Var) &&
3428 1560 : ((Var *) arg)->varattno == InvalidAttrNumber &&
3429 90 : ((Var *) arg)->varlevelsup == 0)
3430 : {
3431 78 : if (rowtype_field_matches(((Var *) arg)->vartype,
3432 78 : fselect->fieldnum,
3433 : fselect->resulttype,
3434 : fselect->resulttypmod,
3435 : fselect->resultcollid))
3436 : {
3437 : Var *newvar;
3438 :
3439 78 : newvar = makeVar(((Var *) arg)->varno,
3440 78 : fselect->fieldnum,
3441 : fselect->resulttype,
3442 : fselect->resulttypmod,
3443 : fselect->resultcollid,
3444 : ((Var *) arg)->varlevelsup);
3445 : /* New Var has same OLD/NEW returning as old one */
3446 78 : newvar->varreturningtype = ((Var *) arg)->varreturningtype;
3447 : /* New Var is nullable by same rels as the old one */
3448 78 : newvar->varnullingrels = ((Var *) arg)->varnullingrels;
3449 78 : return (Node *) newvar;
3450 : }
3451 : }
3452 5584 : if (arg && IsA(arg, RowExpr))
3453 : {
3454 24 : RowExpr *rowexpr = (RowExpr *) arg;
3455 :
3456 48 : if (fselect->fieldnum > 0 &&
3457 24 : fselect->fieldnum <= list_length(rowexpr->args))
3458 : {
3459 24 : Node *fld = (Node *) list_nth(rowexpr->args,
3460 24 : fselect->fieldnum - 1);
3461 :
3462 24 : if (rowtype_field_matches(rowexpr->row_typeid,
3463 24 : fselect->fieldnum,
3464 : fselect->resulttype,
3465 : fselect->resulttypmod,
3466 24 : fselect->resultcollid) &&
3467 48 : fselect->resulttype == exprType(fld) &&
3468 48 : fselect->resulttypmod == exprTypmod(fld) &&
3469 24 : fselect->resultcollid == exprCollation(fld))
3470 24 : return fld;
3471 : }
3472 : }
3473 5560 : newfselect = makeNode(FieldSelect);
3474 5560 : newfselect->arg = (Expr *) arg;
3475 5560 : newfselect->fieldnum = fselect->fieldnum;
3476 5560 : newfselect->resulttype = fselect->resulttype;
3477 5560 : newfselect->resulttypmod = fselect->resulttypmod;
3478 5560 : newfselect->resultcollid = fselect->resultcollid;
3479 5560 : if (arg && IsA(arg, Const))
3480 : {
3481 618 : Const *con = (Const *) arg;
3482 :
3483 618 : if (rowtype_field_matches(con->consttype,
3484 618 : newfselect->fieldnum,
3485 : newfselect->resulttype,
3486 : newfselect->resulttypmod,
3487 : newfselect->resultcollid))
3488 618 : return ece_evaluate_expr(newfselect);
3489 : }
3490 4942 : return (Node *) newfselect;
3491 : }
3492 37620 : case T_NullTest:
3493 : {
3494 37620 : NullTest *ntest = (NullTest *) node;
3495 : NullTest *newntest;
3496 : Node *arg;
3497 :
3498 37620 : arg = eval_const_expressions_mutator((Node *) ntest->arg,
3499 : context);
3500 37618 : if (ntest->argisrow && arg && IsA(arg, RowExpr))
3501 : {
3502 : /*
3503 : * We break ROW(...) IS [NOT] NULL into separate tests on
3504 : * its component fields. This form is usually more
3505 : * efficient to evaluate, as well as being more amenable
3506 : * to optimization.
3507 : */
3508 48 : RowExpr *rarg = (RowExpr *) arg;
3509 48 : List *newargs = NIL;
3510 : ListCell *l;
3511 :
3512 174 : foreach(l, rarg->args)
3513 : {
3514 126 : Node *relem = (Node *) lfirst(l);
3515 :
3516 : /*
3517 : * A constant field refutes the whole NullTest if it's
3518 : * of the wrong nullness; else we can discard it.
3519 : */
3520 126 : if (relem && IsA(relem, Const))
3521 0 : {
3522 0 : Const *carg = (Const *) relem;
3523 :
3524 0 : if (carg->constisnull ?
3525 0 : (ntest->nulltesttype == IS_NOT_NULL) :
3526 0 : (ntest->nulltesttype == IS_NULL))
3527 0 : return makeBoolConst(false, false);
3528 0 : continue;
3529 : }
3530 :
3531 : /*
3532 : * A proven non-nullable field refutes the whole
3533 : * NullTest if the test is IS NULL; else we can
3534 : * discard it.
3535 : */
3536 252 : if (relem &&
3537 126 : expr_is_nonnullable(context->root, (Expr *) relem,
3538 : false))
3539 : {
3540 0 : if (ntest->nulltesttype == IS_NULL)
3541 0 : return makeBoolConst(false, false);
3542 0 : continue;
3543 : }
3544 :
3545 : /*
3546 : * Else, make a scalar (argisrow == false) NullTest
3547 : * for this field. Scalar semantics are required
3548 : * because IS [NOT] NULL doesn't recurse; see comments
3549 : * in ExecEvalRowNullInt().
3550 : */
3551 126 : newntest = makeNode(NullTest);
3552 126 : newntest->arg = (Expr *) relem;
3553 126 : newntest->nulltesttype = ntest->nulltesttype;
3554 126 : newntest->argisrow = false;
3555 126 : newntest->location = ntest->location;
3556 126 : newargs = lappend(newargs, newntest);
3557 : }
3558 : /* If all the inputs were constants, result is TRUE */
3559 48 : if (newargs == NIL)
3560 0 : return makeBoolConst(true, false);
3561 : /* If only one nonconst input, it's the result */
3562 48 : if (list_length(newargs) == 1)
3563 0 : return (Node *) linitial(newargs);
3564 : /* Else we need an AND node */
3565 48 : return (Node *) make_andclause(newargs);
3566 : }
3567 37570 : if (!ntest->argisrow && arg && IsA(arg, Const))
3568 : {
3569 394 : Const *carg = (Const *) arg;
3570 : bool result;
3571 :
3572 394 : switch (ntest->nulltesttype)
3573 : {
3574 328 : case IS_NULL:
3575 328 : result = carg->constisnull;
3576 328 : break;
3577 66 : case IS_NOT_NULL:
3578 66 : result = !carg->constisnull;
3579 66 : break;
3580 0 : default:
3581 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3582 : (int) ntest->nulltesttype);
3583 : result = false; /* keep compiler quiet */
3584 : break;
3585 : }
3586 :
3587 394 : return makeBoolConst(result, false);
3588 : }
3589 73882 : if (!ntest->argisrow && arg &&
3590 36706 : expr_is_nonnullable(context->root, (Expr *) arg, false))
3591 : {
3592 : bool result;
3593 :
3594 654 : switch (ntest->nulltesttype)
3595 : {
3596 160 : case IS_NULL:
3597 160 : result = false;
3598 160 : break;
3599 494 : case IS_NOT_NULL:
3600 494 : result = true;
3601 494 : break;
3602 0 : default:
3603 0 : elog(ERROR, "unrecognized nulltesttype: %d",
3604 : (int) ntest->nulltesttype);
3605 : result = false; /* keep compiler quiet */
3606 : break;
3607 : }
3608 :
3609 654 : return makeBoolConst(result, false);
3610 : }
3611 :
3612 36522 : newntest = makeNode(NullTest);
3613 36522 : newntest->arg = (Expr *) arg;
3614 36522 : newntest->nulltesttype = ntest->nulltesttype;
3615 36522 : newntest->argisrow = ntest->argisrow;
3616 36522 : newntest->location = ntest->location;
3617 36522 : return (Node *) newntest;
3618 : }
3619 1956 : case T_BooleanTest:
3620 : {
3621 : /*
3622 : * This case could be folded into the generic handling used
3623 : * for ArrayExpr etc. But because the simplification logic is
3624 : * so trivial, applying evaluate_expr() to perform it would be
3625 : * a heavy overhead. BooleanTest is probably common enough to
3626 : * justify keeping this bespoke implementation.
3627 : */
3628 1956 : BooleanTest *btest = (BooleanTest *) node;
3629 : BooleanTest *newbtest;
3630 : Node *arg;
3631 :
3632 1956 : arg = eval_const_expressions_mutator((Node *) btest->arg,
3633 : context);
3634 1956 : if (arg && IsA(arg, Const))
3635 : {
3636 222 : Const *carg = (Const *) arg;
3637 : bool result;
3638 :
3639 222 : switch (btest->booltesttype)
3640 : {
3641 0 : case IS_TRUE:
3642 0 : result = (!carg->constisnull &&
3643 0 : DatumGetBool(carg->constvalue));
3644 0 : break;
3645 222 : case IS_NOT_TRUE:
3646 444 : result = (carg->constisnull ||
3647 222 : !DatumGetBool(carg->constvalue));
3648 222 : break;
3649 0 : case IS_FALSE:
3650 0 : result = (!carg->constisnull &&
3651 0 : !DatumGetBool(carg->constvalue));
3652 0 : break;
3653 0 : case IS_NOT_FALSE:
3654 0 : result = (carg->constisnull ||
3655 0 : DatumGetBool(carg->constvalue));
3656 0 : break;
3657 0 : case IS_UNKNOWN:
3658 0 : result = carg->constisnull;
3659 0 : break;
3660 0 : case IS_NOT_UNKNOWN:
3661 0 : result = !carg->constisnull;
3662 0 : break;
3663 0 : default:
3664 0 : elog(ERROR, "unrecognized booltesttype: %d",
3665 : (int) btest->booltesttype);
3666 : result = false; /* keep compiler quiet */
3667 : break;
3668 : }
3669 :
3670 222 : return makeBoolConst(result, false);
3671 : }
3672 :
3673 1734 : newbtest = makeNode(BooleanTest);
3674 1734 : newbtest->arg = (Expr *) arg;
3675 1734 : newbtest->booltesttype = btest->booltesttype;
3676 1734 : newbtest->location = btest->location;
3677 1734 : return (Node *) newbtest;
3678 : }
3679 28040 : case T_CoerceToDomain:
3680 : {
3681 : /*
3682 : * If the domain currently has no constraints, we replace the
3683 : * CoerceToDomain node with a simple RelabelType, which is
3684 : * both far faster to execute and more amenable to later
3685 : * optimization. We must then mark the plan as needing to be
3686 : * rebuilt if the domain's constraints change.
3687 : *
3688 : * Also, in estimation mode, always replace CoerceToDomain
3689 : * nodes, effectively assuming that the coercion will succeed.
3690 : */
3691 28040 : CoerceToDomain *cdomain = (CoerceToDomain *) node;
3692 : CoerceToDomain *newcdomain;
3693 : Node *arg;
3694 :
3695 28040 : arg = eval_const_expressions_mutator((Node *) cdomain->arg,
3696 : context);
3697 28010 : if (context->estimate ||
3698 27962 : !DomainHasConstraints(cdomain->resulttype))
3699 : {
3700 : /* Record dependency, if this isn't estimation mode */
3701 18652 : if (context->root && !context->estimate)
3702 18538 : record_plan_type_dependency(context->root,
3703 : cdomain->resulttype);
3704 :
3705 : /* Generate RelabelType to substitute for CoerceToDomain */
3706 18652 : return applyRelabelType(arg,
3707 : cdomain->resulttype,
3708 : cdomain->resulttypmod,
3709 : cdomain->resultcollid,
3710 : cdomain->coercionformat,
3711 : cdomain->location,
3712 : true);
3713 : }
3714 :
3715 9358 : newcdomain = makeNode(CoerceToDomain);
3716 9358 : newcdomain->arg = (Expr *) arg;
3717 9358 : newcdomain->resulttype = cdomain->resulttype;
3718 9358 : newcdomain->resulttypmod = cdomain->resulttypmod;
3719 9358 : newcdomain->resultcollid = cdomain->resultcollid;
3720 9358 : newcdomain->coercionformat = cdomain->coercionformat;
3721 9358 : newcdomain->location = cdomain->location;
3722 9358 : return (Node *) newcdomain;
3723 : }
3724 4422 : case T_PlaceHolderVar:
3725 :
3726 : /*
3727 : * In estimation mode, just strip the PlaceHolderVar node
3728 : * altogether; this amounts to estimating that the contained value
3729 : * won't be forced to null by an outer join. In regular mode we
3730 : * just use the default behavior (ie, simplify the expression but
3731 : * leave the PlaceHolderVar node intact).
3732 : */
3733 4422 : if (context->estimate)
3734 : {
3735 840 : PlaceHolderVar *phv = (PlaceHolderVar *) node;
3736 :
3737 840 : return eval_const_expressions_mutator((Node *) phv->phexpr,
3738 : context);
3739 : }
3740 3582 : break;
3741 90 : case T_ConvertRowtypeExpr:
3742 : {
3743 90 : ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
3744 : Node *arg;
3745 : ConvertRowtypeExpr *newcre;
3746 :
3747 90 : arg = eval_const_expressions_mutator((Node *) cre->arg,
3748 : context);
3749 :
3750 90 : newcre = makeNode(ConvertRowtypeExpr);
3751 90 : newcre->resulttype = cre->resulttype;
3752 90 : newcre->convertformat = cre->convertformat;
3753 90 : newcre->location = cre->location;
3754 :
3755 : /*
3756 : * In case of a nested ConvertRowtypeExpr, we can convert the
3757 : * leaf row directly to the topmost row format without any
3758 : * intermediate conversions. (This works because
3759 : * ConvertRowtypeExpr is used only for child->parent
3760 : * conversion in inheritance trees, which works by exact match
3761 : * of column name, and a column absent in an intermediate
3762 : * result can't be present in the final result.)
3763 : *
3764 : * No need to check more than one level deep, because the
3765 : * above recursion will have flattened anything else.
3766 : */
3767 90 : if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
3768 : {
3769 12 : ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
3770 :
3771 12 : arg = (Node *) argcre->arg;
3772 :
3773 : /*
3774 : * Make sure an outer implicit conversion can't hide an
3775 : * inner explicit one.
3776 : */
3777 12 : if (newcre->convertformat == COERCE_IMPLICIT_CAST)
3778 0 : newcre->convertformat = argcre->convertformat;
3779 : }
3780 :
3781 90 : newcre->arg = (Expr *) arg;
3782 :
3783 90 : if (arg != NULL && IsA(arg, Const))
3784 18 : return ece_evaluate_expr((Node *) newcre);
3785 72 : return (Node *) newcre;
3786 : }
3787 6851024 : default:
3788 6851024 : break;
3789 : }
3790 :
3791 : /*
3792 : * For any node type not handled above, copy the node unchanged but
3793 : * const-simplify its subexpressions. This is the correct thing for node
3794 : * types whose behavior might change between planning and execution, such
3795 : * as CurrentOfExpr. It's also a safe default for new node types not
3796 : * known to this routine.
3797 : */
3798 6854606 : return ece_generic_processing(node);
3799 : }
3800 :
3801 : /*
3802 : * Subroutine for eval_const_expressions: check for non-Const nodes.
3803 : *
3804 : * We can abort recursion immediately on finding a non-Const node. This is
3805 : * critical for performance, else eval_const_expressions_mutator would take
3806 : * O(N^2) time on non-simplifiable trees. However, we do need to descend
3807 : * into List nodes since expression_tree_walker sometimes invokes the walker
3808 : * function directly on List subtrees.
3809 : */
3810 : static bool
3811 215334 : contain_non_const_walker(Node *node, void *context)
3812 : {
3813 215334 : if (node == NULL)
3814 712 : return false;
3815 214622 : if (IsA(node, Const))
3816 109542 : return false;
3817 105080 : if (IsA(node, List))
3818 36306 : return expression_tree_walker(node, contain_non_const_walker, context);
3819 : /* Otherwise, abort the tree traversal and return true */
3820 68774 : return true;
3821 : }
3822 :
3823 : /*
3824 : * Subroutine for eval_const_expressions: check if a function is OK to evaluate
3825 : */
3826 : static bool
3827 376 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
3828 : {
3829 376 : char provolatile = func_volatile(funcid);
3830 :
3831 : /*
3832 : * Ordinarily we are only allowed to simplify immutable functions. But for
3833 : * purposes of estimation, we consider it okay to simplify functions that
3834 : * are merely stable; the risk that the result might change from planning
3835 : * time to execution time is worth taking in preference to not being able
3836 : * to estimate the value at all.
3837 : */
3838 376 : if (provolatile == PROVOLATILE_IMMUTABLE)
3839 376 : return true;
3840 0 : if (context->estimate && provolatile == PROVOLATILE_STABLE)
3841 0 : return true;
3842 0 : return false;
3843 : }
3844 :
3845 : /*
3846 : * Subroutine for eval_const_expressions: process arguments of an OR clause
3847 : *
3848 : * This includes flattening of nested ORs as well as recursion to
3849 : * eval_const_expressions to simplify the OR arguments.
3850 : *
3851 : * After simplification, OR arguments are handled as follows:
3852 : * non constant: keep
3853 : * FALSE: drop (does not affect result)
3854 : * TRUE: force result to TRUE
3855 : * NULL: keep only one
3856 : * We must keep one NULL input because OR expressions evaluate to NULL when no
3857 : * input is TRUE and at least one is NULL. We don't actually include the NULL
3858 : * here, that's supposed to be done by the caller.
3859 : *
3860 : * The output arguments *haveNull and *forceTrue must be initialized false
3861 : * by the caller. They will be set true if a NULL constant or TRUE constant,
3862 : * respectively, is detected anywhere in the argument list.
3863 : */
3864 : static List *
3865 12836 : simplify_or_arguments(List *args,
3866 : eval_const_expressions_context *context,
3867 : bool *haveNull, bool *forceTrue)
3868 : {
3869 12836 : List *newargs = NIL;
3870 : List *unprocessed_args;
3871 :
3872 : /*
3873 : * We want to ensure that any OR immediately beneath another OR gets
3874 : * flattened into a single OR-list, so as to simplify later reasoning.
3875 : *
3876 : * To avoid stack overflow from recursion of eval_const_expressions, we
3877 : * resort to some tenseness here: we keep a list of not-yet-processed
3878 : * inputs, and handle flattening of nested ORs by prepending to the to-do
3879 : * list instead of recursing. Now that the parser generates N-argument
3880 : * ORs from simple lists, this complexity is probably less necessary than
3881 : * it once was, but we might as well keep the logic.
3882 : */
3883 12836 : unprocessed_args = list_copy(args);
3884 43210 : while (unprocessed_args)
3885 : {
3886 30546 : Node *arg = (Node *) linitial(unprocessed_args);
3887 :
3888 30546 : unprocessed_args = list_delete_first(unprocessed_args);
3889 :
3890 : /* flatten nested ORs as per above comment */
3891 30546 : if (is_orclause(arg))
3892 6 : {
3893 6 : List *subargs = ((BoolExpr *) arg)->args;
3894 6 : List *oldlist = unprocessed_args;
3895 :
3896 6 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
3897 : /* perhaps-overly-tense code to avoid leaking old lists */
3898 6 : list_free(oldlist);
3899 6 : continue;
3900 : }
3901 :
3902 : /* If it's not an OR, simplify it */
3903 30540 : arg = eval_const_expressions_mutator(arg, context);
3904 :
3905 : /*
3906 : * It is unlikely but not impossible for simplification of a non-OR
3907 : * clause to produce an OR. Recheck, but don't be too tense about it
3908 : * since it's not a mainstream case. In particular we don't worry
3909 : * about const-simplifying the input twice, nor about list leakage.
3910 : */
3911 30540 : if (is_orclause(arg))
3912 0 : {
3913 0 : List *subargs = ((BoolExpr *) arg)->args;
3914 :
3915 0 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
3916 0 : continue;
3917 : }
3918 :
3919 : /*
3920 : * OK, we have a const-simplified non-OR argument. Process it per
3921 : * comments above.
3922 : */
3923 30540 : if (IsA(arg, Const))
3924 236 : {
3925 408 : Const *const_input = (Const *) arg;
3926 :
3927 408 : if (const_input->constisnull)
3928 48 : *haveNull = true;
3929 360 : else if (DatumGetBool(const_input->constvalue))
3930 : {
3931 172 : *forceTrue = true;
3932 :
3933 : /*
3934 : * Once we detect a TRUE result we can just exit the loop
3935 : * immediately. However, if we ever add a notion of
3936 : * non-removable functions, we'd need to keep scanning.
3937 : */
3938 172 : return NIL;
3939 : }
3940 : /* otherwise, we can drop the constant-false input */
3941 236 : continue;
3942 : }
3943 :
3944 : /* else emit the simplified arg into the result list */
3945 30132 : newargs = lappend(newargs, arg);
3946 : }
3947 :
3948 12664 : return newargs;
3949 : }
3950 :
3951 : /*
3952 : * Subroutine for eval_const_expressions: process arguments of an AND clause
3953 : *
3954 : * This includes flattening of nested ANDs as well as recursion to
3955 : * eval_const_expressions to simplify the AND arguments.
3956 : *
3957 : * After simplification, AND arguments are handled as follows:
3958 : * non constant: keep
3959 : * TRUE: drop (does not affect result)
3960 : * FALSE: force result to FALSE
3961 : * NULL: keep only one
3962 : * We must keep one NULL input because AND expressions evaluate to NULL when
3963 : * no input is FALSE and at least one is NULL. We don't actually include the
3964 : * NULL here, that's supposed to be done by the caller.
3965 : *
3966 : * The output arguments *haveNull and *forceFalse must be initialized false
3967 : * by the caller. They will be set true if a null constant or false constant,
3968 : * respectively, is detected anywhere in the argument list.
3969 : */
3970 : static List *
3971 145182 : simplify_and_arguments(List *args,
3972 : eval_const_expressions_context *context,
3973 : bool *haveNull, bool *forceFalse)
3974 : {
3975 145182 : List *newargs = NIL;
3976 : List *unprocessed_args;
3977 :
3978 : /* See comments in simplify_or_arguments */
3979 145182 : unprocessed_args = list_copy(args);
3980 533618 : while (unprocessed_args)
3981 : {
3982 389990 : Node *arg = (Node *) linitial(unprocessed_args);
3983 :
3984 389990 : unprocessed_args = list_delete_first(unprocessed_args);
3985 :
3986 : /* flatten nested ANDs as per above comment */
3987 389990 : if (is_andclause(arg))
3988 2112 : {
3989 2112 : List *subargs = ((BoolExpr *) arg)->args;
3990 2112 : List *oldlist = unprocessed_args;
3991 :
3992 2112 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
3993 : /* perhaps-overly-tense code to avoid leaking old lists */
3994 2112 : list_free(oldlist);
3995 2112 : continue;
3996 : }
3997 :
3998 : /* If it's not an AND, simplify it */
3999 387878 : arg = eval_const_expressions_mutator(arg, context);
4000 :
4001 : /*
4002 : * It is unlikely but not impossible for simplification of a non-AND
4003 : * clause to produce an AND. Recheck, but don't be too tense about it
4004 : * since it's not a mainstream case. In particular we don't worry
4005 : * about const-simplifying the input twice, nor about list leakage.
4006 : */
4007 387878 : if (is_andclause(arg))
4008 36 : {
4009 36 : List *subargs = ((BoolExpr *) arg)->args;
4010 :
4011 36 : unprocessed_args = list_concat_copy(subargs, unprocessed_args);
4012 36 : continue;
4013 : }
4014 :
4015 : /*
4016 : * OK, we have a const-simplified non-AND argument. Process it per
4017 : * comments above.
4018 : */
4019 387842 : if (IsA(arg, Const))
4020 2126 : {
4021 3680 : Const *const_input = (Const *) arg;
4022 :
4023 3680 : if (const_input->constisnull)
4024 18 : *haveNull = true;
4025 3662 : else if (!DatumGetBool(const_input->constvalue))
4026 : {
4027 1554 : *forceFalse = true;
4028 :
4029 : /*
4030 : * Once we detect a FALSE result we can just exit the loop
4031 : * immediately. However, if we ever add a notion of
4032 : * non-removable functions, we'd need to keep scanning.
4033 : */
4034 1554 : return NIL;
4035 : }
4036 : /* otherwise, we can drop the constant-true input */
4037 2126 : continue;
4038 : }
4039 :
4040 : /* else emit the simplified arg into the result list */
4041 384162 : newargs = lappend(newargs, arg);
4042 : }
4043 :
4044 143628 : return newargs;
4045 : }
4046 :
4047 : /*
4048 : * Subroutine for eval_const_expressions: try to simplify boolean equality
4049 : * or inequality condition
4050 : *
4051 : * Inputs are the operator OID and the simplified arguments to the operator.
4052 : * Returns a simplified expression if successful, or NULL if cannot
4053 : * simplify the expression.
4054 : *
4055 : * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
4056 : * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
4057 : * This is only marginally useful in itself, but doing it in constant folding
4058 : * ensures that we will recognize these forms as being equivalent in, for
4059 : * example, partial index matching.
4060 : *
4061 : * We come here only if simplify_function has failed; therefore we cannot
4062 : * see two constant inputs, nor a constant-NULL input.
4063 : */
4064 : static Node *
4065 1362 : simplify_boolean_equality(Oid opno, List *args)
4066 : {
4067 : Node *leftop;
4068 : Node *rightop;
4069 :
4070 : Assert(list_length(args) == 2);
4071 1362 : leftop = linitial(args);
4072 1362 : rightop = lsecond(args);
4073 1362 : if (leftop && IsA(leftop, Const))
4074 : {
4075 : Assert(!((Const *) leftop)->constisnull);
4076 0 : if (opno == BooleanEqualOperator)
4077 : {
4078 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4079 0 : return rightop; /* true = foo */
4080 : else
4081 0 : return negate_clause(rightop); /* false = foo */
4082 : }
4083 : else
4084 : {
4085 0 : if (DatumGetBool(((Const *) leftop)->constvalue))
4086 0 : return negate_clause(rightop); /* true <> foo */
4087 : else
4088 0 : return rightop; /* false <> foo */
4089 : }
4090 : }
4091 1362 : if (rightop && IsA(rightop, Const))
4092 : {
4093 : Assert(!((Const *) rightop)->constisnull);
4094 1094 : if (opno == BooleanEqualOperator)
4095 : {
4096 1028 : if (DatumGetBool(((Const *) rightop)->constvalue))
4097 278 : return leftop; /* foo = true */
4098 : else
4099 750 : return negate_clause(leftop); /* foo = false */
4100 : }
4101 : else
4102 : {
4103 66 : if (DatumGetBool(((Const *) rightop)->constvalue))
4104 60 : return negate_clause(leftop); /* foo <> true */
4105 : else
4106 6 : return leftop; /* foo <> false */
4107 : }
4108 : }
4109 268 : return NULL;
4110 : }
4111 :
4112 : /*
4113 : * Subroutine for eval_const_expressions: try to simplify a function call
4114 : * (which might originally have been an operator; we don't care)
4115 : *
4116 : * Inputs are the function OID, actual result type OID (which is needed for
4117 : * polymorphic functions), result typmod, result collation, the input
4118 : * collation to use for the function, the original argument list (not
4119 : * const-simplified yet, unless process_args is false), and some flags;
4120 : * also the context data for eval_const_expressions.
4121 : *
4122 : * Returns a simplified expression if successful, or NULL if cannot
4123 : * simplify the function call.
4124 : *
4125 : * This function is also responsible for converting named-notation argument
4126 : * lists into positional notation and/or adding any needed default argument
4127 : * expressions; which is a bit grotty, but it avoids extra fetches of the
4128 : * function's pg_proc tuple. For this reason, the args list is
4129 : * pass-by-reference. Conversion and const-simplification of the args list
4130 : * will be done even if simplification of the function call itself is not
4131 : * possible.
4132 : */
4133 : static Expr *
4134 1291322 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
4135 : Oid result_collid, Oid input_collid, List **args_p,
4136 : bool funcvariadic, bool process_args, bool allow_non_const,
4137 : eval_const_expressions_context *context)
4138 : {
4139 1291322 : List *args = *args_p;
4140 : HeapTuple func_tuple;
4141 : Form_pg_proc func_form;
4142 : Expr *newexpr;
4143 :
4144 : /*
4145 : * We have three strategies for simplification: execute the function to
4146 : * deliver a constant result, use a transform function to generate a
4147 : * substitute node tree, or expand in-line the body of the function
4148 : * definition (which only works for simple SQL-language functions, but
4149 : * that is a common case). Each case needs access to the function's
4150 : * pg_proc tuple, so fetch it just once.
4151 : *
4152 : * Note: the allow_non_const flag suppresses both the second and third
4153 : * strategies; so if !allow_non_const, simplify_function can only return a
4154 : * Const or NULL. Argument-list rewriting happens anyway, though.
4155 : */
4156 1291322 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
4157 1291322 : if (!HeapTupleIsValid(func_tuple))
4158 0 : elog(ERROR, "cache lookup failed for function %u", funcid);
4159 1291322 : func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
4160 :
4161 : /*
4162 : * Process the function arguments, unless the caller did it already.
4163 : *
4164 : * Here we must deal with named or defaulted arguments, and then
4165 : * recursively apply eval_const_expressions to the whole argument list.
4166 : */
4167 1291322 : if (process_args)
4168 : {
4169 1288810 : args = expand_function_arguments(args, false, result_type, func_tuple);
4170 1288810 : args = (List *) expression_tree_mutator((Node *) args,
4171 : eval_const_expressions_mutator,
4172 : context);
4173 : /* Argument processing done, give it back to the caller */
4174 1288684 : *args_p = args;
4175 : }
4176 :
4177 : /* Now attempt simplification of the function call proper. */
4178 :
4179 1291196 : newexpr = evaluate_function(funcid, result_type, result_typmod,
4180 : result_collid, input_collid,
4181 : args, funcvariadic,
4182 : func_tuple, context);
4183 :
4184 1287256 : if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
4185 : {
4186 : /*
4187 : * Build a SupportRequestSimplify node to pass to the support
4188 : * function, pointing to a dummy FuncExpr node containing the
4189 : * simplified arg list. We use this approach to present a uniform
4190 : * interface to the support function regardless of how the target
4191 : * function is actually being invoked.
4192 : */
4193 : SupportRequestSimplify req;
4194 : FuncExpr fexpr;
4195 :
4196 34674 : fexpr.xpr.type = T_FuncExpr;
4197 34674 : fexpr.funcid = funcid;
4198 34674 : fexpr.funcresulttype = result_type;
4199 34674 : fexpr.funcretset = func_form->proretset;
4200 34674 : fexpr.funcvariadic = funcvariadic;
4201 34674 : fexpr.funcformat = COERCE_EXPLICIT_CALL;
4202 34674 : fexpr.funccollid = result_collid;
4203 34674 : fexpr.inputcollid = input_collid;
4204 34674 : fexpr.args = args;
4205 34674 : fexpr.location = -1;
4206 :
4207 34674 : req.type = T_SupportRequestSimplify;
4208 34674 : req.root = context->root;
4209 34674 : req.fcall = &fexpr;
4210 :
4211 : newexpr = (Expr *)
4212 34674 : DatumGetPointer(OidFunctionCall1(func_form->prosupport,
4213 : PointerGetDatum(&req)));
4214 :
4215 : /* catch a possible API misunderstanding */
4216 : Assert(newexpr != (Expr *) &fexpr);
4217 : }
4218 :
4219 1287256 : if (!newexpr && allow_non_const)
4220 1103434 : newexpr = inline_function(funcid, result_type, result_collid,
4221 : input_collid, args, funcvariadic,
4222 : func_tuple, context);
4223 :
4224 1287242 : ReleaseSysCache(func_tuple);
4225 :
4226 1287242 : return newexpr;
4227 : }
4228 :
4229 : /*
4230 : * simplify_aggref
4231 : * Call the Aggref.aggfnoid's prosupport function to allow it to
4232 : * determine if simplification of the Aggref is possible. Returns the
4233 : * newly simplified node if conversion took place; otherwise, returns the
4234 : * original Aggref.
4235 : *
4236 : * See SupportRequestSimplifyAggref comments in supportnodes.h for further
4237 : * details.
4238 : */
4239 : static Node *
4240 50714 : simplify_aggref(Aggref *aggref, eval_const_expressions_context *context)
4241 : {
4242 50714 : Oid prosupport = get_func_support(aggref->aggfnoid);
4243 :
4244 50714 : if (OidIsValid(prosupport))
4245 : {
4246 : SupportRequestSimplifyAggref req;
4247 : Node *newnode;
4248 :
4249 : /*
4250 : * Build a SupportRequestSimplifyAggref node to pass to the support
4251 : * function.
4252 : */
4253 20630 : req.type = T_SupportRequestSimplifyAggref;
4254 20630 : req.root = context->root;
4255 20630 : req.aggref = aggref;
4256 :
4257 20630 : newnode = (Node *) DatumGetPointer(OidFunctionCall1(prosupport,
4258 : PointerGetDatum(&req)));
4259 :
4260 : /*
4261 : * We expect the support function to return either a new Node or NULL
4262 : * (when simplification isn't possible).
4263 : */
4264 : Assert(newnode != (Node *) aggref || newnode == NULL);
4265 :
4266 20630 : if (newnode != NULL)
4267 698 : return newnode;
4268 : }
4269 :
4270 50016 : return (Node *) aggref;
4271 : }
4272 :
4273 : /*
4274 : * var_is_nonnullable: check to see if the Var cannot be NULL
4275 : *
4276 : * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
4277 : * joins or grouping sets, then we can know that it cannot be NULL.
4278 : *
4279 : * use_rel_info indicates whether the corresponding RelOptInfo is available for
4280 : * use.
4281 : */
4282 : bool
4283 30530 : var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info)
4284 : {
4285 30530 : Bitmapset *notnullattnums = NULL;
4286 :
4287 : Assert(IsA(var, Var));
4288 :
4289 : /* skip upper-level Vars */
4290 30530 : if (var->varlevelsup != 0)
4291 54 : return false;
4292 :
4293 : /* could the Var be nulled by any outer joins or grouping sets? */
4294 30476 : if (!bms_is_empty(var->varnullingrels))
4295 4422 : return false;
4296 :
4297 : /* system columns cannot be NULL */
4298 26054 : if (var->varattno < 0)
4299 36 : return true;
4300 :
4301 : /*
4302 : * Check if the Var is defined as NOT NULL. We retrieve the column NOT
4303 : * NULL constraint information from the corresponding RelOptInfo if it is
4304 : * available; otherwise, we search the hash table for this information.
4305 : */
4306 26018 : if (use_rel_info)
4307 : {
4308 9426 : RelOptInfo *rel = find_base_rel(root, var->varno);
4309 :
4310 9426 : notnullattnums = rel->notnullattnums;
4311 : }
4312 : else
4313 : {
4314 16592 : RangeTblEntry *rte = planner_rt_fetch(var->varno, root);
4315 :
4316 : /*
4317 : * We must skip inheritance parent tables, as some child tables may
4318 : * have a NOT NULL constraint for a column while others may not. This
4319 : * cannot happen with partitioned tables, though.
4320 : */
4321 16592 : if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
4322 156 : return false;
4323 :
4324 16436 : notnullattnums = find_relation_notnullatts(root, rte->relid);
4325 : }
4326 :
4327 51664 : if (var->varattno > 0 &&
4328 25802 : bms_is_member(var->varattno, notnullattnums))
4329 1166 : return true;
4330 :
4331 24696 : return false;
4332 : }
4333 :
4334 : /*
4335 : * expr_is_nonnullable: check to see if the Expr cannot be NULL
4336 : *
4337 : * Returns true iff the given 'expr' cannot produce SQL NULLs.
4338 : *
4339 : * If 'use_rel_info' is true, nullability of Vars is checked via the
4340 : * corresponding RelOptInfo for the given Var. Some callers require
4341 : * nullability information before RelOptInfos are generated. These should
4342 : * pass 'use_rel_info' as false.
4343 : *
4344 : * For now, we support only a limited set of expression types. Support for
4345 : * additional node types can be added in the future.
4346 : */
4347 : bool
4348 53622 : expr_is_nonnullable(PlannerInfo *root, Expr *expr, bool use_rel_info)
4349 : {
4350 : /* since this function recurses, it could be driven to stack overflow */
4351 53622 : check_stack_depth();
4352 :
4353 53622 : switch (nodeTag(expr))
4354 : {
4355 47450 : case T_Var:
4356 : {
4357 47450 : if (root)
4358 30530 : return var_is_nonnullable(root, (Var *) expr, use_rel_info);
4359 : }
4360 16920 : break;
4361 816 : case T_Const:
4362 816 : return !((Const *) expr)->constisnull;
4363 186 : case T_CoalesceExpr:
4364 : {
4365 : /*
4366 : * A CoalesceExpr returns NULL if and only if all its
4367 : * arguments are NULL. Therefore, we can determine that a
4368 : * CoalesceExpr cannot be NULL if at least one of its
4369 : * arguments can be proven non-nullable.
4370 : */
4371 186 : CoalesceExpr *coalesceexpr = (CoalesceExpr *) expr;
4372 :
4373 660 : foreach_ptr(Expr, arg, coalesceexpr->args)
4374 : {
4375 372 : if (expr_is_nonnullable(root, arg, use_rel_info))
4376 42 : return true;
4377 : }
4378 : }
4379 144 : break;
4380 18 : case T_MinMaxExpr:
4381 : {
4382 : /*
4383 : * Like CoalesceExpr, a MinMaxExpr returns NULL only if all
4384 : * its arguments evaluate to NULL.
4385 : */
4386 18 : MinMaxExpr *minmaxexpr = (MinMaxExpr *) expr;
4387 :
4388 60 : foreach_ptr(Expr, arg, minmaxexpr->args)
4389 : {
4390 36 : if (expr_is_nonnullable(root, arg, use_rel_info))
4391 6 : return true;
4392 : }
4393 : }
4394 12 : break;
4395 108 : case T_CaseExpr:
4396 : {
4397 : /*
4398 : * A CASE expression is non-nullable if all branch results are
4399 : * non-nullable. We must also verify that the default result
4400 : * (ELSE) exists and is non-nullable.
4401 : */
4402 108 : CaseExpr *caseexpr = (CaseExpr *) expr;
4403 :
4404 : /* The default result must be present and non-nullable */
4405 108 : if (caseexpr->defresult == NULL ||
4406 108 : !expr_is_nonnullable(root, caseexpr->defresult, use_rel_info))
4407 90 : return false;
4408 :
4409 : /* All branch results must be non-nullable */
4410 30 : foreach_ptr(CaseWhen, casewhen, caseexpr->args)
4411 : {
4412 18 : if (!expr_is_nonnullable(root, casewhen->result, use_rel_info))
4413 12 : return false;
4414 : }
4415 :
4416 6 : return true;
4417 : }
4418 : break;
4419 6 : case T_ArrayExpr:
4420 : {
4421 : /*
4422 : * An ARRAY[] expression always returns a valid Array object,
4423 : * even if it is empty (ARRAY[]) or contains NULLs
4424 : * (ARRAY[NULL]). It never evaluates to a SQL NULL.
4425 : */
4426 6 : return true;
4427 : }
4428 6 : case T_NullTest:
4429 : {
4430 : /*
4431 : * An IS NULL / IS NOT NULL expression always returns a
4432 : * boolean value. It never returns SQL NULL.
4433 : */
4434 6 : return true;
4435 : }
4436 6 : case T_BooleanTest:
4437 : {
4438 : /*
4439 : * A BooleanTest expression always evaluates to a boolean
4440 : * value. It never returns SQL NULL.
4441 : */
4442 6 : return true;
4443 : }
4444 6 : case T_DistinctExpr:
4445 : {
4446 : /*
4447 : * IS DISTINCT FROM never returns NULL, effectively acting as
4448 : * though NULL were a normal data value.
4449 : */
4450 6 : return true;
4451 : }
4452 34 : case T_RelabelType:
4453 : {
4454 : /*
4455 : * RelabelType does not change the nullability of the data.
4456 : * The result is non-nullable if and only if the argument is
4457 : * non-nullable.
4458 : */
4459 34 : return expr_is_nonnullable(root, ((RelabelType *) expr)->arg,
4460 : use_rel_info);
4461 : }
4462 4986 : default:
4463 4986 : break;
4464 : }
4465 :
4466 22062 : return false;
4467 : }
4468 :
4469 : /*
4470 : * expand_function_arguments: convert named-notation args to positional args
4471 : * and/or insert default args, as needed
4472 : *
4473 : * Returns a possibly-transformed version of the args list.
4474 : *
4475 : * If include_out_arguments is true, then the args list and the result
4476 : * include OUT arguments.
4477 : *
4478 : * The expected result type of the call must be given, for sanity-checking
4479 : * purposes. Also, we ask the caller to provide the function's actual
4480 : * pg_proc tuple, not just its OID.
4481 : *
4482 : * If we need to change anything, the input argument list is copied, not
4483 : * modified.
4484 : *
4485 : * Note: this gets applied to operator argument lists too, even though the
4486 : * cases it handles should never occur there. This should be OK since it
4487 : * will fall through very quickly if there's nothing to do.
4488 : */
4489 : List *
4490 1292916 : expand_function_arguments(List *args, bool include_out_arguments,
4491 : Oid result_type, HeapTuple func_tuple)
4492 : {
4493 1292916 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4494 1292916 : Oid *proargtypes = funcform->proargtypes.values;
4495 1292916 : int pronargs = funcform->pronargs;
4496 1292916 : bool has_named_args = false;
4497 : ListCell *lc;
4498 :
4499 : /*
4500 : * If we are asked to match to OUT arguments, then use the proallargtypes
4501 : * array (which includes those); otherwise use proargtypes (which
4502 : * doesn't). Of course, if proallargtypes is null, we always use
4503 : * proargtypes. (Fetching proallargtypes is annoyingly expensive
4504 : * considering that we may have nothing to do here, but fortunately the
4505 : * common case is include_out_arguments == false.)
4506 : */
4507 1292916 : if (include_out_arguments)
4508 : {
4509 : Datum proallargtypes;
4510 : bool isNull;
4511 :
4512 498 : proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
4513 : Anum_pg_proc_proallargtypes,
4514 : &isNull);
4515 498 : if (!isNull)
4516 : {
4517 202 : ArrayType *arr = DatumGetArrayTypeP(proallargtypes);
4518 :
4519 202 : pronargs = ARR_DIMS(arr)[0];
4520 202 : if (ARR_NDIM(arr) != 1 ||
4521 202 : pronargs < 0 ||
4522 202 : ARR_HASNULL(arr) ||
4523 202 : ARR_ELEMTYPE(arr) != OIDOID)
4524 0 : elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
4525 : Assert(pronargs >= funcform->pronargs);
4526 202 : proargtypes = (Oid *) ARR_DATA_PTR(arr);
4527 : }
4528 : }
4529 :
4530 : /* Do we have any named arguments? */
4531 3500944 : foreach(lc, args)
4532 : {
4533 2224176 : Node *arg = (Node *) lfirst(lc);
4534 :
4535 2224176 : if (IsA(arg, NamedArgExpr))
4536 : {
4537 16148 : has_named_args = true;
4538 16148 : break;
4539 : }
4540 : }
4541 :
4542 : /* If so, we must apply reorder_function_arguments */
4543 1292916 : if (has_named_args)
4544 : {
4545 16148 : args = reorder_function_arguments(args, pronargs, func_tuple);
4546 : /* Recheck argument types and add casts if needed */
4547 16148 : recheck_cast_function_args(args, result_type,
4548 : proargtypes, pronargs,
4549 : func_tuple);
4550 : }
4551 1276768 : else if (list_length(args) < pronargs)
4552 : {
4553 : /* No named args, but we seem to be short some defaults */
4554 6468 : args = add_function_defaults(args, pronargs, func_tuple);
4555 : /* Recheck argument types and add casts if needed */
4556 6468 : recheck_cast_function_args(args, result_type,
4557 : proargtypes, pronargs,
4558 : func_tuple);
4559 : }
4560 :
4561 1292916 : return args;
4562 : }
4563 :
4564 : /*
4565 : * reorder_function_arguments: convert named-notation args to positional args
4566 : *
4567 : * This function also inserts default argument values as needed, since it's
4568 : * impossible to form a truly valid positional call without that.
4569 : */
4570 : static List *
4571 16148 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
4572 : {
4573 16148 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4574 16148 : int nargsprovided = list_length(args);
4575 : Node *argarray[FUNC_MAX_ARGS];
4576 : ListCell *lc;
4577 : int i;
4578 :
4579 : Assert(nargsprovided <= pronargs);
4580 16148 : if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
4581 0 : elog(ERROR, "too many function arguments");
4582 16148 : memset(argarray, 0, pronargs * sizeof(Node *));
4583 :
4584 : /* Deconstruct the argument list into an array indexed by argnumber */
4585 16148 : i = 0;
4586 65656 : foreach(lc, args)
4587 : {
4588 49508 : Node *arg = (Node *) lfirst(lc);
4589 :
4590 49508 : if (!IsA(arg, NamedArgExpr))
4591 : {
4592 : /* positional argument, assumed to precede all named args */
4593 : Assert(argarray[i] == NULL);
4594 2468 : argarray[i++] = arg;
4595 : }
4596 : else
4597 : {
4598 47040 : NamedArgExpr *na = (NamedArgExpr *) arg;
4599 :
4600 : Assert(na->argnumber >= 0 && na->argnumber < pronargs);
4601 : Assert(argarray[na->argnumber] == NULL);
4602 47040 : argarray[na->argnumber] = (Node *) na->arg;
4603 : }
4604 : }
4605 :
4606 : /*
4607 : * Fetch default expressions, if needed, and insert into array at proper
4608 : * locations (they aren't necessarily consecutive or all used)
4609 : */
4610 16148 : if (nargsprovided < pronargs)
4611 : {
4612 7524 : List *defaults = fetch_function_defaults(func_tuple);
4613 :
4614 7524 : i = pronargs - funcform->pronargdefaults;
4615 43032 : foreach(lc, defaults)
4616 : {
4617 35508 : if (argarray[i] == NULL)
4618 15238 : argarray[i] = (Node *) lfirst(lc);
4619 35508 : i++;
4620 : }
4621 : }
4622 :
4623 : /* Now reconstruct the args list in proper order */
4624 16148 : args = NIL;
4625 80894 : for (i = 0; i < pronargs; i++)
4626 : {
4627 : Assert(argarray[i] != NULL);
4628 64746 : args = lappend(args, argarray[i]);
4629 : }
4630 :
4631 16148 : return args;
4632 : }
4633 :
4634 : /*
4635 : * add_function_defaults: add missing function arguments from its defaults
4636 : *
4637 : * This is used only when the argument list was positional to begin with,
4638 : * and so we know we just need to add defaults at the end.
4639 : */
4640 : static List *
4641 6468 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
4642 : {
4643 6468 : int nargsprovided = list_length(args);
4644 : List *defaults;
4645 : int ndelete;
4646 :
4647 : /* Get all the default expressions from the pg_proc tuple */
4648 6468 : defaults = fetch_function_defaults(func_tuple);
4649 :
4650 : /* Delete any unused defaults from the list */
4651 6468 : ndelete = nargsprovided + list_length(defaults) - pronargs;
4652 6468 : if (ndelete < 0)
4653 0 : elog(ERROR, "not enough default arguments");
4654 6468 : if (ndelete > 0)
4655 246 : defaults = list_delete_first_n(defaults, ndelete);
4656 :
4657 : /* And form the combined argument list, not modifying the input list */
4658 6468 : return list_concat_copy(args, defaults);
4659 : }
4660 :
4661 : /*
4662 : * fetch_function_defaults: get function's default arguments as expression list
4663 : */
4664 : static List *
4665 13992 : fetch_function_defaults(HeapTuple func_tuple)
4666 : {
4667 : List *defaults;
4668 : Datum proargdefaults;
4669 : char *str;
4670 :
4671 13992 : proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
4672 : Anum_pg_proc_proargdefaults);
4673 13992 : str = TextDatumGetCString(proargdefaults);
4674 13992 : defaults = castNode(List, stringToNode(str));
4675 13992 : pfree(str);
4676 13992 : return defaults;
4677 : }
4678 :
4679 : /*
4680 : * recheck_cast_function_args: recheck function args and typecast as needed
4681 : * after adding defaults.
4682 : *
4683 : * It is possible for some of the defaulted arguments to be polymorphic;
4684 : * therefore we can't assume that the default expressions have the correct
4685 : * data types already. We have to re-resolve polymorphics and do coercion
4686 : * just like the parser did.
4687 : *
4688 : * This should be a no-op if there are no polymorphic arguments,
4689 : * but we do it anyway to be sure.
4690 : *
4691 : * Note: if any casts are needed, the args list is modified in-place;
4692 : * caller should have already copied the list structure.
4693 : */
4694 : static void
4695 22616 : recheck_cast_function_args(List *args, Oid result_type,
4696 : Oid *proargtypes, int pronargs,
4697 : HeapTuple func_tuple)
4698 : {
4699 22616 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4700 : int nargs;
4701 : Oid actual_arg_types[FUNC_MAX_ARGS];
4702 : Oid declared_arg_types[FUNC_MAX_ARGS];
4703 : Oid rettype;
4704 : ListCell *lc;
4705 :
4706 22616 : if (list_length(args) > FUNC_MAX_ARGS)
4707 0 : elog(ERROR, "too many function arguments");
4708 22616 : nargs = 0;
4709 111568 : foreach(lc, args)
4710 : {
4711 88952 : actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
4712 : }
4713 : Assert(nargs == pronargs);
4714 22616 : memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
4715 22616 : rettype = enforce_generic_type_consistency(actual_arg_types,
4716 : declared_arg_types,
4717 : nargs,
4718 : funcform->prorettype,
4719 : false);
4720 : /* let's just check we got the same answer as the parser did ... */
4721 22616 : if (rettype != result_type)
4722 0 : elog(ERROR, "function's resolved result type changed during planning");
4723 :
4724 : /* perform any necessary typecasting of arguments */
4725 22616 : make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
4726 22616 : }
4727 :
4728 : /*
4729 : * evaluate_function: try to pre-evaluate a function call
4730 : *
4731 : * We can do this if the function is strict and has any constant-null inputs
4732 : * (just return a null constant), or if the function is immutable and has all
4733 : * constant inputs (call it and return the result as a Const node). In
4734 : * estimation mode we are willing to pre-evaluate stable functions too.
4735 : *
4736 : * Returns a simplified expression if successful, or NULL if cannot
4737 : * simplify the function.
4738 : */
4739 : static Expr *
4740 1291196 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
4741 : Oid result_collid, Oid input_collid, List *args,
4742 : bool funcvariadic,
4743 : HeapTuple func_tuple,
4744 : eval_const_expressions_context *context)
4745 : {
4746 1291196 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4747 1291196 : bool has_nonconst_input = false;
4748 1291196 : bool has_null_input = false;
4749 : ListCell *arg;
4750 : FuncExpr *newexpr;
4751 :
4752 : /*
4753 : * Can't simplify if it returns a set.
4754 : */
4755 1291196 : if (funcform->proretset)
4756 66112 : return NULL;
4757 :
4758 : /*
4759 : * Can't simplify if it returns RECORD. The immediate problem is that it
4760 : * will be needing an expected tupdesc which we can't supply here.
4761 : *
4762 : * In the case where it has OUT parameters, we could build an expected
4763 : * tupdesc from those, but there may be other gotchas lurking. In
4764 : * particular, if the function were to return NULL, we would produce a
4765 : * null constant with no remaining indication of which concrete record
4766 : * type it is. For now, seems best to leave the function call unreduced.
4767 : */
4768 1225084 : if (funcform->prorettype == RECORDOID)
4769 5562 : return NULL;
4770 :
4771 : /*
4772 : * Check for constant inputs and especially constant-NULL inputs.
4773 : */
4774 3332724 : foreach(arg, args)
4775 : {
4776 2113202 : if (IsA(lfirst(arg), Const))
4777 969860 : has_null_input |= ((Const *) lfirst(arg))->constisnull;
4778 : else
4779 1143342 : has_nonconst_input = true;
4780 : }
4781 :
4782 : /*
4783 : * If the function is strict and has a constant-NULL input, it will never
4784 : * be called at all, so we can replace the call by a NULL constant, even
4785 : * if there are other inputs that aren't constant, and even if the
4786 : * function is not otherwise immutable.
4787 : */
4788 1219522 : if (funcform->proisstrict && has_null_input)
4789 746 : return (Expr *) makeNullConst(result_type, result_typmod,
4790 : result_collid);
4791 :
4792 : /*
4793 : * Otherwise, can simplify only if all inputs are constants. (For a
4794 : * non-strict function, constant NULL inputs are treated the same as
4795 : * constant non-NULL inputs.)
4796 : */
4797 1218776 : if (has_nonconst_input)
4798 881900 : return NULL;
4799 :
4800 : /*
4801 : * Ordinarily we are only allowed to simplify immutable functions. But for
4802 : * purposes of estimation, we consider it okay to simplify functions that
4803 : * are merely stable; the risk that the result might change from planning
4804 : * time to execution time is worth taking in preference to not being able
4805 : * to estimate the value at all.
4806 : */
4807 336876 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
4808 : /* okay */ ;
4809 152578 : else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
4810 : /* okay */ ;
4811 : else
4812 149986 : return NULL;
4813 :
4814 : /*
4815 : * OK, looks like we can simplify this operator/function.
4816 : *
4817 : * Build a new FuncExpr node containing the already-simplified arguments.
4818 : */
4819 186890 : newexpr = makeNode(FuncExpr);
4820 186890 : newexpr->funcid = funcid;
4821 186890 : newexpr->funcresulttype = result_type;
4822 186890 : newexpr->funcretset = false;
4823 186890 : newexpr->funcvariadic = funcvariadic;
4824 186890 : newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
4825 186890 : newexpr->funccollid = result_collid; /* doesn't matter */
4826 186890 : newexpr->inputcollid = input_collid;
4827 186890 : newexpr->args = args;
4828 186890 : newexpr->location = -1;
4829 :
4830 186890 : return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
4831 : result_collid);
4832 : }
4833 :
4834 : /*
4835 : * inline_function: try to expand a function call inline
4836 : *
4837 : * If the function is a sufficiently simple SQL-language function
4838 : * (just "SELECT expression"), then we can inline it and avoid the rather
4839 : * high per-call overhead of SQL functions. Furthermore, this can expose
4840 : * opportunities for constant-folding within the function expression.
4841 : *
4842 : * We have to beware of some special cases however. A directly or
4843 : * indirectly recursive function would cause us to recurse forever,
4844 : * so we keep track of which functions we are already expanding and
4845 : * do not re-expand them. Also, if a parameter is used more than once
4846 : * in the SQL-function body, we require it not to contain any volatile
4847 : * functions (volatiles might deliver inconsistent answers) nor to be
4848 : * unreasonably expensive to evaluate. The expensiveness check not only
4849 : * prevents us from doing multiple evaluations of an expensive parameter
4850 : * at runtime, but is a safety value to limit growth of an expression due
4851 : * to repeated inlining.
4852 : *
4853 : * We must also beware of changing the volatility or strictness status of
4854 : * functions by inlining them.
4855 : *
4856 : * Also, at the moment we can't inline functions returning RECORD. This
4857 : * doesn't work in the general case because it discards information such
4858 : * as OUT-parameter declarations.
4859 : *
4860 : * Also, context-dependent expression nodes in the argument list are trouble.
4861 : *
4862 : * Returns a simplified expression if successful, or NULL if cannot
4863 : * simplify the function.
4864 : */
4865 : static Expr *
4866 1103434 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
4867 : Oid input_collid, List *args,
4868 : bool funcvariadic,
4869 : HeapTuple func_tuple,
4870 : eval_const_expressions_context *context)
4871 : {
4872 1103434 : Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
4873 : char *src;
4874 : Datum tmp;
4875 : bool isNull;
4876 : MemoryContext oldcxt;
4877 : MemoryContext mycxt;
4878 : inline_error_callback_arg callback_arg;
4879 : ErrorContextCallback sqlerrcontext;
4880 : FuncExpr *fexpr;
4881 : SQLFunctionParseInfoPtr pinfo;
4882 : TupleDesc rettupdesc;
4883 : ParseState *pstate;
4884 : List *raw_parsetree_list;
4885 : List *querytree_list;
4886 : Query *querytree;
4887 : Node *newexpr;
4888 : int *usecounts;
4889 : ListCell *arg;
4890 : int i;
4891 :
4892 : /*
4893 : * Forget it if the function is not SQL-language or has other showstopper
4894 : * properties. (The prokind and nargs checks are just paranoia.)
4895 : */
4896 1103434 : if (funcform->prolang != SQLlanguageId ||
4897 8284 : funcform->prokind != PROKIND_FUNCTION ||
4898 8284 : funcform->prosecdef ||
4899 8272 : funcform->proretset ||
4900 6846 : funcform->prorettype == RECORDOID ||
4901 13038 : !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
4902 6498 : funcform->pronargs != list_length(args))
4903 1096936 : return NULL;
4904 :
4905 : /* Check for recursive function, and give up trying to expand if so */
4906 6498 : if (list_member_oid(context->active_fns, funcid))
4907 12 : return NULL;
4908 :
4909 : /* Check permission to call function (fail later, if not) */
4910 6486 : if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
4911 20 : return NULL;
4912 :
4913 : /* Check whether a plugin wants to hook function entry/exit */
4914 6466 : if (FmgrHookIsNeeded(funcid))
4915 0 : return NULL;
4916 :
4917 : /*
4918 : * Make a temporary memory context, so that we don't leak all the stuff
4919 : * that parsing might create.
4920 : */
4921 6466 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
4922 : "inline_function",
4923 : ALLOCSET_DEFAULT_SIZES);
4924 6466 : oldcxt = MemoryContextSwitchTo(mycxt);
4925 :
4926 : /*
4927 : * We need a dummy FuncExpr node containing the already-simplified
4928 : * arguments. (In some cases we don't really need it, but building it is
4929 : * cheap enough that it's not worth contortions to avoid.)
4930 : */
4931 6466 : fexpr = makeNode(FuncExpr);
4932 6466 : fexpr->funcid = funcid;
4933 6466 : fexpr->funcresulttype = result_type;
4934 6466 : fexpr->funcretset = false;
4935 6466 : fexpr->funcvariadic = funcvariadic;
4936 6466 : fexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
4937 6466 : fexpr->funccollid = result_collid; /* doesn't matter */
4938 6466 : fexpr->inputcollid = input_collid;
4939 6466 : fexpr->args = args;
4940 6466 : fexpr->location = -1;
4941 :
4942 : /* Fetch the function body */
4943 6466 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
4944 6466 : src = TextDatumGetCString(tmp);
4945 :
4946 : /*
4947 : * Setup error traceback support for ereport(). This is so that we can
4948 : * finger the function that bad information came from.
4949 : */
4950 6466 : callback_arg.proname = NameStr(funcform->proname);
4951 6466 : callback_arg.prosrc = src;
4952 :
4953 6466 : sqlerrcontext.callback = sql_inline_error_callback;
4954 6466 : sqlerrcontext.arg = &callback_arg;
4955 6466 : sqlerrcontext.previous = error_context_stack;
4956 6466 : error_context_stack = &sqlerrcontext;
4957 :
4958 : /* If we have prosqlbody, pay attention to that not prosrc */
4959 6466 : tmp = SysCacheGetAttr(PROCOID,
4960 : func_tuple,
4961 : Anum_pg_proc_prosqlbody,
4962 : &isNull);
4963 6466 : if (!isNull)
4964 : {
4965 : Node *n;
4966 : List *query_list;
4967 :
4968 3398 : n = stringToNode(TextDatumGetCString(tmp));
4969 3398 : if (IsA(n, List))
4970 2562 : query_list = linitial_node(List, castNode(List, n));
4971 : else
4972 836 : query_list = list_make1(n);
4973 3398 : if (list_length(query_list) != 1)
4974 6 : goto fail;
4975 3392 : querytree = linitial(query_list);
4976 :
4977 : /*
4978 : * Because we'll insist below that the querytree have an empty rtable
4979 : * and no sublinks, it cannot have any relation references that need
4980 : * to be locked or rewritten. So we can omit those steps.
4981 : */
4982 : }
4983 : else
4984 : {
4985 : /* Set up to handle parameters while parsing the function body. */
4986 3068 : pinfo = prepare_sql_fn_parse_info(func_tuple,
4987 : (Node *) fexpr,
4988 : input_collid);
4989 :
4990 : /*
4991 : * We just do parsing and parse analysis, not rewriting, because
4992 : * rewriting will not affect table-free-SELECT-only queries, which is
4993 : * all that we care about. Also, we can punt as soon as we detect
4994 : * more than one command in the function body.
4995 : */
4996 3068 : raw_parsetree_list = pg_parse_query(src);
4997 3068 : if (list_length(raw_parsetree_list) != 1)
4998 58 : goto fail;
4999 :
5000 3010 : pstate = make_parsestate(NULL);
5001 3010 : pstate->p_sourcetext = src;
5002 3010 : sql_fn_parser_setup(pstate, pinfo);
5003 :
5004 3010 : querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
5005 :
5006 3004 : free_parsestate(pstate);
5007 : }
5008 :
5009 : /*
5010 : * The single command must be a simple "SELECT expression".
5011 : *
5012 : * Note: if you change the tests involved in this, see also plpgsql's
5013 : * exec_simple_check_plan(). That generally needs to have the same idea
5014 : * of what's a "simple expression", so that inlining a function that
5015 : * previously wasn't inlined won't change plpgsql's conclusion.
5016 : */
5017 6396 : if (!IsA(querytree, Query) ||
5018 6396 : querytree->commandType != CMD_SELECT ||
5019 6274 : querytree->hasAggs ||
5020 6124 : querytree->hasWindowFuncs ||
5021 6124 : querytree->hasTargetSRFs ||
5022 6124 : querytree->hasSubLinks ||
5023 5392 : querytree->cteList ||
5024 5392 : querytree->rtable ||
5025 3500 : querytree->jointree->fromlist ||
5026 3500 : querytree->jointree->quals ||
5027 3500 : querytree->groupClause ||
5028 3500 : querytree->groupingSets ||
5029 3500 : querytree->havingQual ||
5030 3500 : querytree->windowClause ||
5031 3500 : querytree->distinctClause ||
5032 3500 : querytree->sortClause ||
5033 3500 : querytree->limitOffset ||
5034 3500 : querytree->limitCount ||
5035 6864 : querytree->setOperations ||
5036 3432 : list_length(querytree->targetList) != 1)
5037 3024 : goto fail;
5038 :
5039 : /* If the function result is composite, resolve it */
5040 3372 : (void) get_expr_result_type((Node *) fexpr,
5041 : NULL,
5042 : &rettupdesc);
5043 :
5044 : /*
5045 : * Make sure the function (still) returns what it's declared to. This
5046 : * will raise an error if wrong, but that's okay since the function would
5047 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5048 : * a coercion if needed to make the tlist expression match the declared
5049 : * type of the function.
5050 : *
5051 : * Note: we do not try this until we have verified that no rewriting was
5052 : * needed; that's probably not important, but let's be careful.
5053 : */
5054 3372 : querytree_list = list_make1(querytree);
5055 3372 : if (check_sql_fn_retval(list_make1(querytree_list),
5056 : result_type, rettupdesc,
5057 3372 : funcform->prokind,
5058 : false))
5059 12 : goto fail; /* reject whole-tuple-result cases */
5060 :
5061 : /*
5062 : * Given the tests above, check_sql_fn_retval shouldn't have decided to
5063 : * inject a projection step, but let's just make sure.
5064 : */
5065 3354 : if (querytree != linitial(querytree_list))
5066 0 : goto fail;
5067 :
5068 : /* Now we can grab the tlist expression */
5069 3354 : newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
5070 :
5071 : /*
5072 : * If the SQL function returns VOID, we can only inline it if it is a
5073 : * SELECT of an expression returning VOID (ie, it's just a redirection to
5074 : * another VOID-returning function). In all non-VOID-returning cases,
5075 : * check_sql_fn_retval should ensure that newexpr returns the function's
5076 : * declared result type, so this test shouldn't fail otherwise; but we may
5077 : * as well cope gracefully if it does.
5078 : */
5079 3354 : if (exprType(newexpr) != result_type)
5080 18 : goto fail;
5081 :
5082 : /*
5083 : * Additional validity checks on the expression. It mustn't be more
5084 : * volatile than the surrounding function (this is to avoid breaking hacks
5085 : * that involve pretending a function is immutable when it really ain't).
5086 : * If the surrounding function is declared strict, then the expression
5087 : * must contain only strict constructs and must use all of the function
5088 : * parameters (this is overkill, but an exact analysis is hard).
5089 : */
5090 4048 : if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
5091 712 : contain_mutable_functions(newexpr))
5092 12 : goto fail;
5093 4300 : else if (funcform->provolatile == PROVOLATILE_STABLE &&
5094 976 : contain_volatile_functions(newexpr))
5095 0 : goto fail;
5096 :
5097 5032 : if (funcform->proisstrict &&
5098 1708 : contain_nonstrict_functions(newexpr))
5099 46 : goto fail;
5100 :
5101 : /*
5102 : * If any parameter expression contains a context-dependent node, we can't
5103 : * inline, for fear of putting such a node into the wrong context.
5104 : */
5105 3278 : if (contain_context_dependent_node((Node *) args))
5106 6 : goto fail;
5107 :
5108 : /*
5109 : * We may be able to do it; there are still checks on parameter usage to
5110 : * make, but those are most easily done in combination with the actual
5111 : * substitution of the inputs. So start building expression with inputs
5112 : * substituted.
5113 : */
5114 3272 : usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
5115 3272 : newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
5116 : args, usecounts);
5117 :
5118 : /* Now check for parameter usage */
5119 3272 : i = 0;
5120 8682 : foreach(arg, args)
5121 : {
5122 5410 : Node *param = lfirst(arg);
5123 :
5124 5410 : if (usecounts[i] == 0)
5125 : {
5126 : /* Param not used at all: uncool if func is strict */
5127 288 : if (funcform->proisstrict)
5128 0 : goto fail;
5129 : }
5130 5122 : else if (usecounts[i] != 1)
5131 : {
5132 : /* Param used multiple times: uncool if expensive or volatile */
5133 : QualCost eval_cost;
5134 :
5135 : /*
5136 : * We define "expensive" as "contains any subplan or more than 10
5137 : * operators". Note that the subplan search has to be done
5138 : * explicitly, since cost_qual_eval() will barf on unplanned
5139 : * subselects.
5140 : */
5141 462 : if (contain_subplans(param))
5142 0 : goto fail;
5143 462 : cost_qual_eval(&eval_cost, list_make1(param), NULL);
5144 462 : if (eval_cost.startup + eval_cost.per_tuple >
5145 462 : 10 * cpu_operator_cost)
5146 0 : goto fail;
5147 :
5148 : /*
5149 : * Check volatility last since this is more expensive than the
5150 : * above tests
5151 : */
5152 462 : if (contain_volatile_functions(param))
5153 0 : goto fail;
5154 : }
5155 5410 : i++;
5156 : }
5157 :
5158 : /*
5159 : * Whew --- we can make the substitution. Copy the modified expression
5160 : * out of the temporary memory context, and clean up.
5161 : */
5162 3272 : MemoryContextSwitchTo(oldcxt);
5163 :
5164 3272 : newexpr = copyObject(newexpr);
5165 :
5166 3272 : MemoryContextDelete(mycxt);
5167 :
5168 : /*
5169 : * If the result is of a collatable type, force the result to expose the
5170 : * correct collation. In most cases this does not matter, but it's
5171 : * possible that the function result is used directly as a sort key or in
5172 : * other places where we expect exprCollation() to tell the truth.
5173 : */
5174 3272 : if (OidIsValid(result_collid))
5175 : {
5176 1482 : Oid exprcoll = exprCollation(newexpr);
5177 :
5178 1482 : if (OidIsValid(exprcoll) && exprcoll != result_collid)
5179 : {
5180 36 : CollateExpr *newnode = makeNode(CollateExpr);
5181 :
5182 36 : newnode->arg = (Expr *) newexpr;
5183 36 : newnode->collOid = result_collid;
5184 36 : newnode->location = -1;
5185 :
5186 36 : newexpr = (Node *) newnode;
5187 : }
5188 : }
5189 :
5190 : /*
5191 : * Since there is now no trace of the function in the plan tree, we must
5192 : * explicitly record the plan's dependency on the function.
5193 : */
5194 3272 : if (context->root)
5195 3048 : record_plan_function_dependency(context->root, funcid);
5196 :
5197 : /*
5198 : * Recursively try to simplify the modified expression. Here we must add
5199 : * the current function to the context list of active functions.
5200 : */
5201 3272 : context->active_fns = lappend_oid(context->active_fns, funcid);
5202 3272 : newexpr = eval_const_expressions_mutator(newexpr, context);
5203 3270 : context->active_fns = list_delete_last(context->active_fns);
5204 :
5205 3270 : error_context_stack = sqlerrcontext.previous;
5206 :
5207 3270 : return (Expr *) newexpr;
5208 :
5209 : /* Here if func is not inlinable: release temp memory and return NULL */
5210 3182 : fail:
5211 3182 : MemoryContextSwitchTo(oldcxt);
5212 3182 : MemoryContextDelete(mycxt);
5213 3182 : error_context_stack = sqlerrcontext.previous;
5214 :
5215 3182 : return NULL;
5216 : }
5217 :
5218 : /*
5219 : * Replace Param nodes by appropriate actual parameters
5220 : */
5221 : static Node *
5222 3272 : substitute_actual_parameters(Node *expr, int nargs, List *args,
5223 : int *usecounts)
5224 : {
5225 : substitute_actual_parameters_context context;
5226 :
5227 3272 : context.nargs = nargs;
5228 3272 : context.args = args;
5229 3272 : context.usecounts = usecounts;
5230 :
5231 3272 : return substitute_actual_parameters_mutator(expr, &context);
5232 : }
5233 :
5234 : static Node *
5235 19076 : substitute_actual_parameters_mutator(Node *node,
5236 : substitute_actual_parameters_context *context)
5237 : {
5238 19076 : if (node == NULL)
5239 564 : return NULL;
5240 18512 : if (IsA(node, Param))
5241 : {
5242 5620 : Param *param = (Param *) node;
5243 :
5244 5620 : if (param->paramkind != PARAM_EXTERN)
5245 0 : elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
5246 5620 : if (param->paramid <= 0 || param->paramid > context->nargs)
5247 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5248 :
5249 : /* Count usage of parameter */
5250 5620 : context->usecounts[param->paramid - 1]++;
5251 :
5252 : /* Select the appropriate actual arg and replace the Param with it */
5253 : /* We don't need to copy at this time (it'll get done later) */
5254 5620 : return list_nth(context->args, param->paramid - 1);
5255 : }
5256 12892 : return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
5257 : }
5258 :
5259 : /*
5260 : * error context callback to let us supply a call-stack traceback
5261 : */
5262 : static void
5263 20 : sql_inline_error_callback(void *arg)
5264 : {
5265 20 : inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
5266 : int syntaxerrposition;
5267 :
5268 : /* If it's a syntax error, convert to internal syntax error report */
5269 20 : syntaxerrposition = geterrposition();
5270 20 : if (syntaxerrposition > 0)
5271 : {
5272 6 : errposition(0);
5273 6 : internalerrposition(syntaxerrposition);
5274 6 : internalerrquery(callback_arg->prosrc);
5275 : }
5276 :
5277 20 : errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
5278 20 : }
5279 :
5280 : /*
5281 : * evaluate_expr: pre-evaluate a constant expression
5282 : *
5283 : * We use the executor's routine ExecEvalExpr() to avoid duplication of
5284 : * code and ensure we get the same result as the executor would get.
5285 : */
5286 : Expr *
5287 221904 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
5288 : Oid result_collation)
5289 : {
5290 : EState *estate;
5291 : ExprState *exprstate;
5292 : MemoryContext oldcontext;
5293 : Datum const_val;
5294 : bool const_is_null;
5295 : int16 resultTypLen;
5296 : bool resultTypByVal;
5297 :
5298 : /*
5299 : * To use the executor, we need an EState.
5300 : */
5301 221904 : estate = CreateExecutorState();
5302 :
5303 : /* We can use the estate's working context to avoid memory leaks. */
5304 221904 : oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
5305 :
5306 : /* Make sure any opfuncids are filled in. */
5307 221904 : fix_opfuncids((Node *) expr);
5308 :
5309 : /*
5310 : * Prepare expr for execution. (Note: we can't use ExecPrepareExpr
5311 : * because it'd result in recursively invoking eval_const_expressions.)
5312 : */
5313 221904 : exprstate = ExecInitExpr(expr, NULL);
5314 :
5315 : /*
5316 : * And evaluate it.
5317 : *
5318 : * It is OK to use a default econtext because none of the ExecEvalExpr()
5319 : * code used in this situation will use econtext. That might seem
5320 : * fortuitous, but it's not so unreasonable --- a constant expression does
5321 : * not depend on context, by definition, n'est ce pas?
5322 : */
5323 221880 : const_val = ExecEvalExprSwitchContext(exprstate,
5324 221880 : GetPerTupleExprContext(estate),
5325 : &const_is_null);
5326 :
5327 : /* Get info needed about result datatype */
5328 217922 : get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
5329 :
5330 : /* Get back to outer memory context */
5331 217922 : MemoryContextSwitchTo(oldcontext);
5332 :
5333 : /*
5334 : * Must copy result out of sub-context used by expression eval.
5335 : *
5336 : * Also, if it's varlena, forcibly detoast it. This protects us against
5337 : * storing TOAST pointers into plans that might outlive the referenced
5338 : * data. (makeConst would handle detoasting anyway, but it's worth a few
5339 : * extra lines here so that we can do the copy and detoast in one step.)
5340 : */
5341 217922 : if (!const_is_null)
5342 : {
5343 216406 : if (resultTypLen == -1)
5344 86726 : const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
5345 : else
5346 129680 : const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
5347 : }
5348 :
5349 : /* Release all the junk we just created */
5350 217922 : FreeExecutorState(estate);
5351 :
5352 : /*
5353 : * Make the constant result node.
5354 : */
5355 217922 : return (Expr *) makeConst(result_type, result_typmod, result_collation,
5356 : resultTypLen,
5357 : const_val, const_is_null,
5358 : resultTypByVal);
5359 : }
5360 :
5361 :
5362 : /*
5363 : * inline_function_in_from
5364 : * Attempt to "inline" a function in the FROM clause.
5365 : *
5366 : * "rte" is an RTE_FUNCTION rangetable entry. If it represents a call of a
5367 : * function that can be inlined, expand the function and return the
5368 : * substitute Query structure. Otherwise, return NULL.
5369 : *
5370 : * We assume that the RTE's expression has already been put through
5371 : * eval_const_expressions(), which among other things will take care of
5372 : * default arguments and named-argument notation.
5373 : *
5374 : * This has a good deal of similarity to inline_function(), but that's
5375 : * for the general-expression case, and there are enough differences to
5376 : * justify separate functions.
5377 : */
5378 : Query *
5379 53264 : inline_function_in_from(PlannerInfo *root, RangeTblEntry *rte)
5380 : {
5381 : RangeTblFunction *rtfunc;
5382 : FuncExpr *fexpr;
5383 : Oid func_oid;
5384 : HeapTuple func_tuple;
5385 : Form_pg_proc funcform;
5386 : MemoryContext oldcxt;
5387 : MemoryContext mycxt;
5388 : Datum tmp;
5389 : char *src;
5390 : inline_error_callback_arg callback_arg;
5391 : ErrorContextCallback sqlerrcontext;
5392 53264 : Query *querytree = NULL;
5393 :
5394 : Assert(rte->rtekind == RTE_FUNCTION);
5395 :
5396 : /*
5397 : * Guard against infinite recursion during expansion by checking for stack
5398 : * overflow. (There's no need to do more.)
5399 : */
5400 53264 : check_stack_depth();
5401 :
5402 : /* Fail if the RTE has ORDINALITY - we don't implement that here. */
5403 53264 : if (rte->funcordinality)
5404 954 : return NULL;
5405 :
5406 : /* Fail if RTE isn't a single, simple FuncExpr */
5407 52310 : if (list_length(rte->functions) != 1)
5408 74 : return NULL;
5409 52236 : rtfunc = (RangeTblFunction *) linitial(rte->functions);
5410 :
5411 52236 : if (!IsA(rtfunc->funcexpr, FuncExpr))
5412 414 : return NULL;
5413 51822 : fexpr = (FuncExpr *) rtfunc->funcexpr;
5414 :
5415 51822 : func_oid = fexpr->funcid;
5416 :
5417 : /*
5418 : * Refuse to inline if the arguments contain any volatile functions or
5419 : * sub-selects. Volatile functions are rejected because inlining may
5420 : * result in the arguments being evaluated multiple times, risking a
5421 : * change in behavior. Sub-selects are rejected partly for implementation
5422 : * reasons (pushing them down another level might change their behavior)
5423 : * and partly because they're likely to be expensive and so multiple
5424 : * evaluation would be bad.
5425 : */
5426 103430 : if (contain_volatile_functions((Node *) fexpr->args) ||
5427 51608 : contain_subplans((Node *) fexpr->args))
5428 450 : return NULL;
5429 :
5430 : /* Check permission to call function (fail later, if not) */
5431 51372 : if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
5432 12 : return NULL;
5433 :
5434 : /* Check whether a plugin wants to hook function entry/exit */
5435 51360 : if (FmgrHookIsNeeded(func_oid))
5436 0 : return NULL;
5437 :
5438 : /*
5439 : * OK, let's take a look at the function's pg_proc entry.
5440 : */
5441 51360 : func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
5442 51360 : if (!HeapTupleIsValid(func_tuple))
5443 0 : elog(ERROR, "cache lookup failed for function %u", func_oid);
5444 51360 : funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
5445 :
5446 : /*
5447 : * If the function SETs any configuration parameters, inlining would cause
5448 : * us to miss making those changes.
5449 : */
5450 51360 : if (!heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
5451 : {
5452 16 : ReleaseSysCache(func_tuple);
5453 16 : return NULL;
5454 : }
5455 :
5456 : /*
5457 : * Make a temporary memory context, so that we don't leak all the stuff
5458 : * that parsing and rewriting might create. If we succeed, we'll copy
5459 : * just the finished query tree back up to the caller's context.
5460 : */
5461 51344 : mycxt = AllocSetContextCreate(CurrentMemoryContext,
5462 : "inline_function_in_from",
5463 : ALLOCSET_DEFAULT_SIZES);
5464 51344 : oldcxt = MemoryContextSwitchTo(mycxt);
5465 :
5466 : /* Fetch the function body */
5467 51344 : tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
5468 51344 : src = TextDatumGetCString(tmp);
5469 :
5470 : /*
5471 : * If the function has an attached support function that can handle
5472 : * SupportRequestInlineInFrom, then attempt to inline with that.
5473 : */
5474 51344 : if (funcform->prosupport)
5475 : {
5476 : SupportRequestInlineInFrom req;
5477 :
5478 17556 : req.type = T_SupportRequestInlineInFrom;
5479 17556 : req.root = root;
5480 17556 : req.rtfunc = rtfunc;
5481 17556 : req.proc = func_tuple;
5482 :
5483 : querytree = (Query *)
5484 17556 : DatumGetPointer(OidFunctionCall1(funcform->prosupport,
5485 : PointerGetDatum(&req)));
5486 : }
5487 :
5488 : /*
5489 : * Setup error traceback support for ereport(). This is so that we can
5490 : * finger the function that bad information came from. We don't install
5491 : * this while running the support function, since it'd be likely to do the
5492 : * wrong thing: any parse errors reported during that are very likely not
5493 : * against the raw function source text.
5494 : */
5495 51344 : callback_arg.proname = NameStr(funcform->proname);
5496 51344 : callback_arg.prosrc = src;
5497 :
5498 51344 : sqlerrcontext.callback = sql_inline_error_callback;
5499 51344 : sqlerrcontext.arg = &callback_arg;
5500 51344 : sqlerrcontext.previous = error_context_stack;
5501 51344 : error_context_stack = &sqlerrcontext;
5502 :
5503 : /*
5504 : * If SupportRequestInlineInFrom didn't work, try our built-in inlining
5505 : * mechanism.
5506 : */
5507 51344 : if (!querytree)
5508 51320 : querytree = inline_sql_function_in_from(root, rtfunc, fexpr,
5509 : func_tuple, funcform, src);
5510 :
5511 51338 : if (!querytree)
5512 51092 : goto fail; /* no luck there either, fail */
5513 :
5514 : /*
5515 : * The result had better be a SELECT Query.
5516 : */
5517 : Assert(IsA(querytree, Query));
5518 : Assert(querytree->commandType == CMD_SELECT);
5519 :
5520 : /*
5521 : * Looks good --- substitute parameters into the query.
5522 : */
5523 246 : querytree = substitute_actual_parameters_in_from(querytree,
5524 246 : funcform->pronargs,
5525 : fexpr->args);
5526 :
5527 : /*
5528 : * Copy the modified query out of the temporary memory context, and clean
5529 : * up.
5530 : */
5531 246 : MemoryContextSwitchTo(oldcxt);
5532 :
5533 246 : querytree = copyObject(querytree);
5534 :
5535 246 : MemoryContextDelete(mycxt);
5536 246 : error_context_stack = sqlerrcontext.previous;
5537 246 : ReleaseSysCache(func_tuple);
5538 :
5539 : /*
5540 : * We don't have to fix collations here because the upper query is already
5541 : * parsed, ie, the collations in the RTE are what count.
5542 : */
5543 :
5544 : /*
5545 : * Since there is now no trace of the function in the plan tree, we must
5546 : * explicitly record the plan's dependency on the function.
5547 : */
5548 246 : record_plan_function_dependency(root, func_oid);
5549 :
5550 : /*
5551 : * We must also notice if the inserted query adds a dependency on the
5552 : * calling role due to RLS quals.
5553 : */
5554 246 : if (querytree->hasRowSecurity)
5555 72 : root->glob->dependsOnRole = true;
5556 :
5557 246 : return querytree;
5558 :
5559 : /* Here if func is not inlinable: release temp memory and return NULL */
5560 51092 : fail:
5561 51092 : MemoryContextSwitchTo(oldcxt);
5562 51092 : MemoryContextDelete(mycxt);
5563 51092 : error_context_stack = sqlerrcontext.previous;
5564 51092 : ReleaseSysCache(func_tuple);
5565 :
5566 51092 : return NULL;
5567 : }
5568 :
5569 : /*
5570 : * inline_sql_function_in_from
5571 : *
5572 : * This implements inline_function_in_from for SQL-language functions.
5573 : * Returns NULL if the function couldn't be inlined.
5574 : *
5575 : * The division of labor between here and inline_function_in_from is based
5576 : * on the rule that inline_function_in_from should make all checks that are
5577 : * certain to be required in both this case and the support-function case.
5578 : * Support functions might also want to make checks analogous to the ones
5579 : * made here, but then again they might not, or they might just assume that
5580 : * the function they are attached to can validly be inlined.
5581 : */
5582 : static Query *
5583 51320 : inline_sql_function_in_from(PlannerInfo *root,
5584 : RangeTblFunction *rtfunc,
5585 : FuncExpr *fexpr,
5586 : HeapTuple func_tuple,
5587 : Form_pg_proc funcform,
5588 : const char *src)
5589 : {
5590 : Datum sqlbody;
5591 : bool isNull;
5592 : List *querytree_list;
5593 : Query *querytree;
5594 : TypeFuncClass functypclass;
5595 : TupleDesc rettupdesc;
5596 :
5597 : /*
5598 : * The function must be declared to return a set, else inlining would
5599 : * change the results if the contained SELECT didn't return exactly one
5600 : * row.
5601 : */
5602 51320 : if (!fexpr->funcretset)
5603 8704 : return NULL;
5604 :
5605 : /*
5606 : * Forget it if the function is not SQL-language or has other showstopper
5607 : * properties. In particular it mustn't be declared STRICT, since we
5608 : * couldn't enforce that. It also mustn't be VOLATILE, because that is
5609 : * supposed to cause it to be executed with its own snapshot, rather than
5610 : * sharing the snapshot of the calling query. We also disallow returning
5611 : * SETOF VOID, because inlining would result in exposing the actual result
5612 : * of the function's last SELECT, which should not happen in that case.
5613 : * (Rechecking prokind, proretset, and pronargs is just paranoia.)
5614 : */
5615 42616 : if (funcform->prolang != SQLlanguageId ||
5616 648 : funcform->prokind != PROKIND_FUNCTION ||
5617 648 : funcform->proisstrict ||
5618 588 : funcform->provolatile == PROVOLATILE_VOLATILE ||
5619 234 : funcform->prorettype == VOIDOID ||
5620 228 : funcform->prosecdef ||
5621 228 : !funcform->proretset ||
5622 228 : list_length(fexpr->args) != funcform->pronargs)
5623 42388 : return NULL;
5624 :
5625 : /* If we have prosqlbody, pay attention to that not prosrc */
5626 228 : sqlbody = SysCacheGetAttr(PROCOID,
5627 : func_tuple,
5628 : Anum_pg_proc_prosqlbody,
5629 : &isNull);
5630 228 : if (!isNull)
5631 : {
5632 : Node *n;
5633 :
5634 12 : n = stringToNode(TextDatumGetCString(sqlbody));
5635 12 : if (IsA(n, List))
5636 12 : querytree_list = linitial_node(List, castNode(List, n));
5637 : else
5638 0 : querytree_list = list_make1(n);
5639 12 : if (list_length(querytree_list) != 1)
5640 0 : return NULL;
5641 12 : querytree = linitial(querytree_list);
5642 :
5643 : /* Acquire necessary locks, then apply rewriter. */
5644 12 : AcquireRewriteLocks(querytree, true, false);
5645 12 : querytree_list = pg_rewrite_query(querytree);
5646 12 : if (list_length(querytree_list) != 1)
5647 0 : return NULL;
5648 12 : querytree = linitial(querytree_list);
5649 : }
5650 : else
5651 : {
5652 : SQLFunctionParseInfoPtr pinfo;
5653 : List *raw_parsetree_list;
5654 :
5655 : /*
5656 : * Set up to handle parameters while parsing the function body. We
5657 : * can use the FuncExpr just created as the input for
5658 : * prepare_sql_fn_parse_info.
5659 : */
5660 216 : pinfo = prepare_sql_fn_parse_info(func_tuple,
5661 : (Node *) fexpr,
5662 : fexpr->inputcollid);
5663 :
5664 : /*
5665 : * Parse, analyze, and rewrite (unlike inline_function(), we can't
5666 : * skip rewriting here). We can fail as soon as we find more than one
5667 : * query, though.
5668 : */
5669 216 : raw_parsetree_list = pg_parse_query(src);
5670 216 : if (list_length(raw_parsetree_list) != 1)
5671 0 : return NULL;
5672 :
5673 216 : querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
5674 : src,
5675 : (ParserSetupHook) sql_fn_parser_setup,
5676 : pinfo, NULL);
5677 216 : if (list_length(querytree_list) != 1)
5678 0 : return NULL;
5679 216 : querytree = linitial(querytree_list);
5680 : }
5681 :
5682 : /*
5683 : * Also resolve the actual function result tupdesc, if composite. If we
5684 : * have a coldeflist, believe that; otherwise use get_expr_result_type.
5685 : * (This logic should match ExecInitFunctionScan.)
5686 : */
5687 228 : if (rtfunc->funccolnames != NIL)
5688 : {
5689 24 : functypclass = TYPEFUNC_RECORD;
5690 24 : rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
5691 24 : rtfunc->funccoltypes,
5692 24 : rtfunc->funccoltypmods,
5693 24 : rtfunc->funccolcollations);
5694 : }
5695 : else
5696 204 : functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
5697 :
5698 : /*
5699 : * The single command must be a plain SELECT.
5700 : */
5701 228 : if (!IsA(querytree, Query) ||
5702 228 : querytree->commandType != CMD_SELECT)
5703 0 : return NULL;
5704 :
5705 : /*
5706 : * Make sure the function (still) returns what it's declared to. This
5707 : * will raise an error if wrong, but that's okay since the function would
5708 : * fail at runtime anyway. Note that check_sql_fn_retval will also insert
5709 : * coercions if needed to make the tlist expression(s) match the declared
5710 : * type of the function. We also ask it to insert dummy NULL columns for
5711 : * any dropped columns in rettupdesc, so that the elements of the modified
5712 : * tlist match up to the attribute numbers.
5713 : *
5714 : * If the function returns a composite type, don't inline unless the check
5715 : * shows it's returning a whole tuple result; otherwise what it's
5716 : * returning is a single composite column which is not what we need.
5717 : */
5718 228 : if (!check_sql_fn_retval(list_make1(querytree_list),
5719 : fexpr->funcresulttype, rettupdesc,
5720 228 : funcform->prokind,
5721 90 : true) &&
5722 90 : (functypclass == TYPEFUNC_COMPOSITE ||
5723 90 : functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
5724 : functypclass == TYPEFUNC_RECORD))
5725 0 : return NULL; /* reject not-whole-tuple-result cases */
5726 :
5727 : /*
5728 : * check_sql_fn_retval might've inserted a projection step, but that's
5729 : * fine; just make sure we use the upper Query.
5730 : */
5731 222 : querytree = linitial_node(Query, querytree_list);
5732 :
5733 222 : return querytree;
5734 : }
5735 :
5736 : /*
5737 : * Replace Param nodes by appropriate actual parameters
5738 : *
5739 : * This is just enough different from substitute_actual_parameters()
5740 : * that it needs its own code.
5741 : */
5742 : static Query *
5743 246 : substitute_actual_parameters_in_from(Query *expr, int nargs, List *args)
5744 : {
5745 : substitute_actual_parameters_in_from_context context;
5746 :
5747 246 : context.nargs = nargs;
5748 246 : context.args = args;
5749 246 : context.sublevels_up = 1;
5750 :
5751 246 : return query_tree_mutator(expr,
5752 : substitute_actual_parameters_in_from_mutator,
5753 : &context,
5754 : 0);
5755 : }
5756 :
5757 : static Node *
5758 8838 : substitute_actual_parameters_in_from_mutator(Node *node,
5759 : substitute_actual_parameters_in_from_context *context)
5760 : {
5761 : Node *result;
5762 :
5763 8838 : if (node == NULL)
5764 4980 : return NULL;
5765 3858 : if (IsA(node, Query))
5766 : {
5767 150 : context->sublevels_up++;
5768 150 : result = (Node *) query_tree_mutator((Query *) node,
5769 : substitute_actual_parameters_in_from_mutator,
5770 : context,
5771 : 0);
5772 150 : context->sublevels_up--;
5773 150 : return result;
5774 : }
5775 3708 : if (IsA(node, Param))
5776 : {
5777 114 : Param *param = (Param *) node;
5778 :
5779 114 : if (param->paramkind == PARAM_EXTERN)
5780 : {
5781 114 : if (param->paramid <= 0 || param->paramid > context->nargs)
5782 0 : elog(ERROR, "invalid paramid: %d", param->paramid);
5783 :
5784 : /*
5785 : * Since the parameter is being inserted into a subquery, we must
5786 : * adjust levels.
5787 : */
5788 114 : result = copyObject(list_nth(context->args, param->paramid - 1));
5789 114 : IncrementVarSublevelsUp(result, context->sublevels_up, 0);
5790 114 : return result;
5791 : }
5792 : }
5793 3594 : return expression_tree_mutator(node,
5794 : substitute_actual_parameters_in_from_mutator,
5795 : context);
5796 : }
5797 :
5798 : /*
5799 : * pull_paramids
5800 : * Returns a Bitmapset containing the paramids of all Params in 'expr'.
5801 : */
5802 : Bitmapset *
5803 1958 : pull_paramids(Expr *expr)
5804 : {
5805 1958 : Bitmapset *result = NULL;
5806 :
5807 1958 : (void) pull_paramids_walker((Node *) expr, &result);
5808 :
5809 1958 : return result;
5810 : }
5811 :
5812 : static bool
5813 4352 : pull_paramids_walker(Node *node, Bitmapset **context)
5814 : {
5815 4352 : if (node == NULL)
5816 18 : return false;
5817 4334 : if (IsA(node, Param))
5818 : {
5819 2020 : Param *param = (Param *) node;
5820 :
5821 2020 : *context = bms_add_member(*context, param->paramid);
5822 2020 : return false;
5823 : }
5824 2314 : return expression_tree_walker(node, pull_paramids_walker, context);
5825 : }
5826 :
5827 : /*
5828 : * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
5829 : * whether at least one of the expressions is not Const. When it's false,
5830 : * the array constant is built directly; otherwise, we have to build a child
5831 : * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
5832 : * expression tree.
5833 : */
5834 : ScalarArrayOpExpr *
5835 1134 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
5836 : Oid inputcollid, List *exprs, bool haveNonConst)
5837 : {
5838 1134 : Node *arrayNode = NULL;
5839 1134 : ScalarArrayOpExpr *saopexpr = NULL;
5840 1134 : Oid arraytype = get_array_type(coltype);
5841 :
5842 1134 : if (!OidIsValid(arraytype))
5843 0 : return NULL;
5844 :
5845 : /*
5846 : * Assemble an array from the list of constants. It seems more profitable
5847 : * to build a const array. But in the presence of other nodes, we don't
5848 : * have a specific value here and must employ an ArrayExpr instead.
5849 : */
5850 1134 : if (haveNonConst)
5851 : {
5852 96 : ArrayExpr *arrayExpr = makeNode(ArrayExpr);
5853 :
5854 : /* array_collid will be set by parse_collate.c */
5855 96 : arrayExpr->element_typeid = coltype;
5856 96 : arrayExpr->array_typeid = arraytype;
5857 96 : arrayExpr->multidims = false;
5858 96 : arrayExpr->elements = exprs;
5859 96 : arrayExpr->location = -1;
5860 :
5861 96 : arrayNode = (Node *) arrayExpr;
5862 : }
5863 : else
5864 : {
5865 : int16 typlen;
5866 : bool typbyval;
5867 : char typalign;
5868 : Datum *elems;
5869 : bool *nulls;
5870 1038 : int i = 0;
5871 : ArrayType *arrayConst;
5872 1038 : int dims[1] = {list_length(exprs)};
5873 1038 : int lbs[1] = {1};
5874 :
5875 1038 : get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
5876 :
5877 1038 : elems = palloc_array(Datum, list_length(exprs));
5878 1038 : nulls = palloc_array(bool, list_length(exprs));
5879 4638 : foreach_node(Const, value, exprs)
5880 : {
5881 2562 : elems[i] = value->constvalue;
5882 2562 : nulls[i++] = value->constisnull;
5883 : }
5884 :
5885 1038 : arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
5886 : coltype, typlen, typbyval, typalign);
5887 1038 : arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
5888 : -1, PointerGetDatum(arrayConst),
5889 : false, false);
5890 :
5891 1038 : pfree(elems);
5892 1038 : pfree(nulls);
5893 1038 : list_free(exprs);
5894 : }
5895 :
5896 : /* Build the SAOP expression node */
5897 1134 : saopexpr = makeNode(ScalarArrayOpExpr);
5898 1134 : saopexpr->opno = oper;
5899 1134 : saopexpr->opfuncid = get_opcode(oper);
5900 1134 : saopexpr->hashfuncid = InvalidOid;
5901 1134 : saopexpr->negfuncid = InvalidOid;
5902 1134 : saopexpr->useOr = true;
5903 1134 : saopexpr->inputcollid = inputcollid;
5904 1134 : saopexpr->args = list_make2(leftexpr, arrayNode);
5905 1134 : saopexpr->location = -1;
5906 :
5907 1134 : return saopexpr;
5908 : }
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