PostgreSQL Source Code  git master
parse_clause.c
Go to the documentation of this file.
1 /*-------------------------------------------------------------------------
2  *
3  * parse_clause.c
4  * handle clauses in parser
5  *
6  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/parser/parse_clause.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 
16 #include "postgres.h"
17 
18 #include "access/htup_details.h"
19 #include "access/nbtree.h"
20 #include "access/table.h"
21 #include "access/tsmapi.h"
22 #include "catalog/catalog.h"
23 #include "catalog/pg_am.h"
24 #include "catalog/pg_amproc.h"
25 #include "catalog/pg_constraint.h"
26 #include "catalog/pg_type.h"
27 #include "commands/defrem.h"
28 #include "miscadmin.h"
29 #include "nodes/makefuncs.h"
30 #include "nodes/nodeFuncs.h"
31 #include "optimizer/optimizer.h"
32 #include "parser/analyze.h"
33 #include "parser/parse_clause.h"
34 #include "parser/parse_coerce.h"
35 #include "parser/parse_collate.h"
36 #include "parser/parse_expr.h"
37 #include "parser/parse_func.h"
38 #include "parser/parse_oper.h"
39 #include "parser/parse_relation.h"
40 #include "parser/parse_target.h"
41 #include "parser/parse_type.h"
42 #include "parser/parser.h"
43 #include "parser/parsetree.h"
44 #include "rewrite/rewriteManip.h"
45 #include "utils/builtins.h"
46 #include "utils/catcache.h"
47 #include "utils/guc.h"
48 #include "utils/lsyscache.h"
49 #include "utils/rel.h"
50 #include "utils/syscache.h"
51 
52 
53 static int extractRemainingColumns(ParseState *pstate,
54  ParseNamespaceColumn *src_nscolumns,
55  List *src_colnames,
56  List **src_colnos,
57  List **res_colnames, List **res_colvars,
58  ParseNamespaceColumn *res_nscolumns);
60  List *leftVars, List *rightVars);
62  List *namespace);
65  RangeSubselect *r);
67  RangeFunction *r);
69  RangeTableFunc *rtf);
71  RangeTableSample *rts);
73  RangeVar *rv);
74 static Node *transformFromClauseItem(ParseState *pstate, Node *n,
75  ParseNamespaceItem **top_nsitem,
76  List **namespace);
77 static Var *buildVarFromNSColumn(ParseState *pstate,
78  ParseNamespaceColumn *nscol);
79 static Node *buildMergedJoinVar(ParseState *pstate, JoinType jointype,
80  Var *l_colvar, Var *r_colvar);
81 static void markRelsAsNulledBy(ParseState *pstate, Node *n, int jindex);
82 static void setNamespaceColumnVisibility(List *namespace, bool cols_visible);
83 static void setNamespaceLateralState(List *namespace,
84  bool lateral_only, bool lateral_ok);
85 static void checkExprIsVarFree(ParseState *pstate, Node *n,
86  const char *constructName);
88  List **tlist, ParseExprKind exprKind);
90  List **tlist, ParseExprKind exprKind);
91 static int get_matching_location(int sortgroupref,
92  List *sortgrouprefs, List *exprs);
94  Relation heapRel);
95 static List *addTargetToGroupList(ParseState *pstate, TargetEntry *tle,
96  List *grouplist, List *targetlist, int location);
97 static WindowClause *findWindowClause(List *wclist, const char *name);
98 static Node *transformFrameOffset(ParseState *pstate, int frameOptions,
99  Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc,
100  Node *clause);
101 
102 
103 /*
104  * transformFromClause -
105  * Process the FROM clause and add items to the query's range table,
106  * joinlist, and namespace.
107  *
108  * Note: we assume that the pstate's p_rtable, p_joinlist, and p_namespace
109  * lists were initialized to NIL when the pstate was created.
110  * We will add onto any entries already present --- this is needed for rule
111  * processing, as well as for UPDATE and DELETE.
112  */
113 void
115 {
116  ListCell *fl;
117 
118  /*
119  * The grammar will have produced a list of RangeVars, RangeSubselects,
120  * RangeFunctions, and/or JoinExprs. Transform each one (possibly adding
121  * entries to the rtable), check for duplicate refnames, and then add it
122  * to the joinlist and namespace.
123  *
124  * Note we must process the items left-to-right for proper handling of
125  * LATERAL references.
126  */
127  foreach(fl, frmList)
128  {
129  Node *n = lfirst(fl);
130  ParseNamespaceItem *nsitem;
131  List *namespace;
132 
133  n = transformFromClauseItem(pstate, n,
134  &nsitem,
135  &namespace);
136 
137  checkNameSpaceConflicts(pstate, pstate->p_namespace, namespace);
138 
139  /* Mark the new namespace items as visible only to LATERAL */
140  setNamespaceLateralState(namespace, true, true);
141 
142  pstate->p_joinlist = lappend(pstate->p_joinlist, n);
143  pstate->p_namespace = list_concat(pstate->p_namespace, namespace);
144  }
145 
146  /*
147  * We're done parsing the FROM list, so make all namespace items
148  * unconditionally visible. Note that this will also reset lateral_only
149  * for any namespace items that were already present when we were called;
150  * but those should have been that way already.
151  */
152  setNamespaceLateralState(pstate->p_namespace, false, true);
153 }
154 
155 /*
156  * setTargetTable
157  * Add the target relation of INSERT/UPDATE/DELETE/MERGE to the range table,
158  * and make the special links to it in the ParseState.
159  *
160  * We also open the target relation and acquire a write lock on it.
161  * This must be done before processing the FROM list, in case the target
162  * is also mentioned as a source relation --- we want to be sure to grab
163  * the write lock before any read lock.
164  *
165  * If alsoSource is true, add the target to the query's joinlist and
166  * namespace. For INSERT, we don't want the target to be joined to;
167  * it's a destination of tuples, not a source. MERGE is actually
168  * both, but we'll add it separately to joinlist and namespace, so
169  * doing nothing (like INSERT) is correct here. For UPDATE/DELETE,
170  * we do need to scan or join the target. (NOTE: we do not bother
171  * to check for namespace conflict; we assume that the namespace was
172  * initially empty in these cases.)
173  *
174  * Finally, we mark the relation as requiring the permissions specified
175  * by requiredPerms.
176  *
177  * Returns the rangetable index of the target relation.
178  */
179 int
180 setTargetTable(ParseState *pstate, RangeVar *relation,
181  bool inh, bool alsoSource, AclMode requiredPerms)
182 {
183  ParseNamespaceItem *nsitem;
184 
185  /*
186  * ENRs hide tables of the same name, so we need to check for them first.
187  * In contrast, CTEs don't hide tables (for this purpose).
188  */
189  if (relation->schemaname == NULL &&
190  scanNameSpaceForENR(pstate, relation->relname))
191  ereport(ERROR,
192  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
193  errmsg("relation \"%s\" cannot be the target of a modifying statement",
194  relation->relname)));
195 
196  /* Close old target; this could only happen for multi-action rules */
197  if (pstate->p_target_relation != NULL)
199 
200  /*
201  * Open target rel and grab suitable lock (which we will hold till end of
202  * transaction).
203  *
204  * free_parsestate() will eventually do the corresponding table_close(),
205  * but *not* release the lock.
206  */
207  pstate->p_target_relation = parserOpenTable(pstate, relation,
209 
210  /*
211  * Now build an RTE and a ParseNamespaceItem.
212  */
213  nsitem = addRangeTableEntryForRelation(pstate, pstate->p_target_relation,
215  relation->alias, inh, false);
216 
217  /* remember the RTE/nsitem as being the query target */
218  pstate->p_target_nsitem = nsitem;
219 
220  /*
221  * Override addRangeTableEntry's default ACL_SELECT permissions check, and
222  * instead mark target table as requiring exactly the specified
223  * permissions.
224  *
225  * If we find an explicit reference to the rel later during parse
226  * analysis, we will add the ACL_SELECT bit back again; see
227  * markVarForSelectPriv and its callers.
228  */
229  nsitem->p_perminfo->requiredPerms = requiredPerms;
230 
231  /*
232  * If UPDATE/DELETE, add table to joinlist and namespace.
233  */
234  if (alsoSource)
235  addNSItemToQuery(pstate, nsitem, true, true, true);
236 
237  return nsitem->p_rtindex;
238 }
239 
240 /*
241  * Extract all not-in-common columns from column lists of a source table
242  *
243  * src_nscolumns and src_colnames describe the source table.
244  *
245  * *src_colnos initially contains the column numbers of the already-merged
246  * columns. We add to it the column number of each additional column.
247  * Also append to *res_colnames the name of each additional column,
248  * append to *res_colvars a Var for each additional column, and copy the
249  * columns' nscolumns data into res_nscolumns[] (which is caller-allocated
250  * space that had better be big enough).
251  *
252  * Returns the number of columns added.
253  */
254 static int
256  ParseNamespaceColumn *src_nscolumns,
257  List *src_colnames,
258  List **src_colnos,
259  List **res_colnames, List **res_colvars,
260  ParseNamespaceColumn *res_nscolumns)
261 {
262  int colcount = 0;
263  Bitmapset *prevcols;
264  int attnum;
265  ListCell *lc;
266 
267  /*
268  * While we could just test "list_member_int(*src_colnos, attnum)" to
269  * detect already-merged columns in the loop below, that would be O(N^2)
270  * for a wide input table. Instead build a bitmapset of just the merged
271  * USING columns, which we won't add to within the main loop.
272  */
273  prevcols = NULL;
274  foreach(lc, *src_colnos)
275  {
276  prevcols = bms_add_member(prevcols, lfirst_int(lc));
277  }
278 
279  attnum = 0;
280  foreach(lc, src_colnames)
281  {
282  char *colname = strVal(lfirst(lc));
283 
284  attnum++;
285  /* Non-dropped and not already merged? */
286  if (colname[0] != '\0' && !bms_is_member(attnum, prevcols))
287  {
288  /* Yes, so emit it as next output column */
289  *src_colnos = lappend_int(*src_colnos, attnum);
290  *res_colnames = lappend(*res_colnames, lfirst(lc));
291  *res_colvars = lappend(*res_colvars,
292  buildVarFromNSColumn(pstate,
293  src_nscolumns + attnum - 1));
294  /* Copy the input relation's nscolumn data for this column */
295  res_nscolumns[colcount] = src_nscolumns[attnum - 1];
296  colcount++;
297  }
298  }
299  return colcount;
300 }
301 
302 /* transformJoinUsingClause()
303  * Build a complete ON clause from a partially-transformed USING list.
304  * We are given lists of nodes representing left and right match columns.
305  * Result is a transformed qualification expression.
306  */
307 static Node *
309  List *leftVars, List *rightVars)
310 {
311  Node *result;
312  List *andargs = NIL;
313  ListCell *lvars,
314  *rvars;
315 
316  /*
317  * We cheat a little bit here by building an untransformed operator tree
318  * whose leaves are the already-transformed Vars. This requires collusion
319  * from transformExpr(), which normally could be expected to complain
320  * about already-transformed subnodes. However, this does mean that we
321  * have to mark the columns as requiring SELECT privilege for ourselves;
322  * transformExpr() won't do it.
323  */
324  forboth(lvars, leftVars, rvars, rightVars)
325  {
326  Var *lvar = (Var *) lfirst(lvars);
327  Var *rvar = (Var *) lfirst(rvars);
328  A_Expr *e;
329 
330  /* Require read access to the join variables */
331  markVarForSelectPriv(pstate, lvar);
332  markVarForSelectPriv(pstate, rvar);
333 
334  /* Now create the lvar = rvar join condition */
335  e = makeSimpleA_Expr(AEXPR_OP, "=",
336  (Node *) copyObject(lvar), (Node *) copyObject(rvar),
337  -1);
338 
339  /* Prepare to combine into an AND clause, if multiple join columns */
340  andargs = lappend(andargs, e);
341  }
342 
343  /* Only need an AND if there's more than one join column */
344  if (list_length(andargs) == 1)
345  result = (Node *) linitial(andargs);
346  else
347  result = (Node *) makeBoolExpr(AND_EXPR, andargs, -1);
348 
349  /*
350  * Since the references are already Vars, and are certainly from the input
351  * relations, we don't have to go through the same pushups that
352  * transformJoinOnClause() does. Just invoke transformExpr() to fix up
353  * the operators, and we're done.
354  */
355  result = transformExpr(pstate, result, EXPR_KIND_JOIN_USING);
356 
357  result = coerce_to_boolean(pstate, result, "JOIN/USING");
358 
359  return result;
360 }
361 
362 /* transformJoinOnClause()
363  * Transform the qual conditions for JOIN/ON.
364  * Result is a transformed qualification expression.
365  */
366 static Node *
368 {
369  Node *result;
370  List *save_namespace;
371 
372  /*
373  * The namespace that the join expression should see is just the two
374  * subtrees of the JOIN plus any outer references from upper pstate
375  * levels. Temporarily set this pstate's namespace accordingly. (We need
376  * not check for refname conflicts, because transformFromClauseItem()
377  * already did.) All namespace items are marked visible regardless of
378  * LATERAL state.
379  */
380  setNamespaceLateralState(namespace, false, true);
381 
382  save_namespace = pstate->p_namespace;
383  pstate->p_namespace = namespace;
384 
385  result = transformWhereClause(pstate, j->quals,
386  EXPR_KIND_JOIN_ON, "JOIN/ON");
387 
388  pstate->p_namespace = save_namespace;
389 
390  return result;
391 }
392 
393 /*
394  * transformTableEntry --- transform a RangeVar (simple relation reference)
395  */
396 static ParseNamespaceItem *
398 {
399  /* addRangeTableEntry does all the work */
400  return addRangeTableEntry(pstate, r, r->alias, r->inh, true);
401 }
402 
403 /*
404  * transformRangeSubselect --- transform a sub-SELECT appearing in FROM
405  */
406 static ParseNamespaceItem *
408 {
409  Query *query;
410 
411  /*
412  * Set p_expr_kind to show this parse level is recursing to a subselect.
413  * We can't be nested within any expression, so don't need save-restore
414  * logic here.
415  */
416  Assert(pstate->p_expr_kind == EXPR_KIND_NONE);
418 
419  /*
420  * If the subselect is LATERAL, make lateral_only names of this level
421  * visible to it. (LATERAL can't nest within a single pstate level, so we
422  * don't need save/restore logic here.)
423  */
424  Assert(!pstate->p_lateral_active);
425  pstate->p_lateral_active = r->lateral;
426 
427  /*
428  * Analyze and transform the subquery. Note that if the subquery doesn't
429  * have an alias, it can't be explicitly selected for locking, but locking
430  * might still be required (if there is an all-tables locking clause).
431  */
432  query = parse_sub_analyze(r->subquery, pstate, NULL,
433  isLockedRefname(pstate,
434  r->alias == NULL ? NULL :
435  r->alias->aliasname),
436  true);
437 
438  /* Restore state */
439  pstate->p_lateral_active = false;
440  pstate->p_expr_kind = EXPR_KIND_NONE;
441 
442  /*
443  * Check that we got a SELECT. Anything else should be impossible given
444  * restrictions of the grammar, but check anyway.
445  */
446  if (!IsA(query, Query) ||
447  query->commandType != CMD_SELECT)
448  elog(ERROR, "unexpected non-SELECT command in subquery in FROM");
449 
450  /*
451  * OK, build an RTE and nsitem for the subquery.
452  */
453  return addRangeTableEntryForSubquery(pstate,
454  query,
455  r->alias,
456  r->lateral,
457  true);
458 }
459 
460 
461 /*
462  * transformRangeFunction --- transform a function call appearing in FROM
463  */
464 static ParseNamespaceItem *
466 {
467  List *funcexprs = NIL;
468  List *funcnames = NIL;
469  List *coldeflists = NIL;
470  bool is_lateral;
471  ListCell *lc;
472 
473  /*
474  * We make lateral_only names of this level visible, whether or not the
475  * RangeFunction is explicitly marked LATERAL. This is needed for SQL
476  * spec compliance in the case of UNNEST(), and seems useful on
477  * convenience grounds for all functions in FROM.
478  *
479  * (LATERAL can't nest within a single pstate level, so we don't need
480  * save/restore logic here.)
481  */
482  Assert(!pstate->p_lateral_active);
483  pstate->p_lateral_active = true;
484 
485  /*
486  * Transform the raw expressions.
487  *
488  * While transforming, also save function names for possible use as alias
489  * and column names. We use the same transformation rules as for a SELECT
490  * output expression. For a FuncCall node, the result will be the
491  * function name, but it is possible for the grammar to hand back other
492  * node types.
493  *
494  * We have to get this info now, because FigureColname only works on raw
495  * parsetrees. Actually deciding what to do with the names is left up to
496  * addRangeTableEntryForFunction.
497  *
498  * Likewise, collect column definition lists if there were any. But
499  * complain if we find one here and the RangeFunction has one too.
500  */
501  foreach(lc, r->functions)
502  {
503  List *pair = (List *) lfirst(lc);
504  Node *fexpr;
505  List *coldeflist;
506  Node *newfexpr;
507  Node *last_srf;
508 
509  /* Disassemble the function-call/column-def-list pairs */
510  Assert(list_length(pair) == 2);
511  fexpr = (Node *) linitial(pair);
512  coldeflist = (List *) lsecond(pair);
513 
514  /*
515  * If we find a function call unnest() with more than one argument and
516  * no special decoration, transform it into separate unnest() calls on
517  * each argument. This is a kluge, for sure, but it's less nasty than
518  * other ways of implementing the SQL-standard UNNEST() syntax.
519  *
520  * If there is any decoration (including a coldeflist), we don't
521  * transform, which probably means a no-such-function error later. We
522  * could alternatively throw an error right now, but that doesn't seem
523  * tremendously helpful. If someone is using any such decoration,
524  * then they're not using the SQL-standard syntax, and they're more
525  * likely expecting an un-tweaked function call.
526  *
527  * Note: the transformation changes a non-schema-qualified unnest()
528  * function name into schema-qualified pg_catalog.unnest(). This
529  * choice is also a bit debatable, but it seems reasonable to force
530  * use of built-in unnest() when we make this transformation.
531  */
532  if (IsA(fexpr, FuncCall))
533  {
534  FuncCall *fc = (FuncCall *) fexpr;
535 
536  if (list_length(fc->funcname) == 1 &&
537  strcmp(strVal(linitial(fc->funcname)), "unnest") == 0 &&
538  list_length(fc->args) > 1 &&
539  fc->agg_order == NIL &&
540  fc->agg_filter == NULL &&
541  fc->over == NULL &&
542  !fc->agg_star &&
543  !fc->agg_distinct &&
544  !fc->func_variadic &&
545  coldeflist == NIL)
546  {
547  ListCell *lc2;
548 
549  foreach(lc2, fc->args)
550  {
551  Node *arg = (Node *) lfirst(lc2);
552  FuncCall *newfc;
553 
554  last_srf = pstate->p_last_srf;
555 
556  newfc = makeFuncCall(SystemFuncName("unnest"),
557  list_make1(arg),
559  fc->location);
560 
561  newfexpr = transformExpr(pstate, (Node *) newfc,
563 
564  /* nodeFunctionscan.c requires SRFs to be at top level */
565  if (pstate->p_last_srf != last_srf &&
566  pstate->p_last_srf != newfexpr)
567  ereport(ERROR,
568  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
569  errmsg("set-returning functions must appear at top level of FROM"),
570  parser_errposition(pstate,
571  exprLocation(pstate->p_last_srf))));
572 
573  funcexprs = lappend(funcexprs, newfexpr);
574 
575  funcnames = lappend(funcnames,
576  FigureColname((Node *) newfc));
577 
578  /* coldeflist is empty, so no error is possible */
579 
580  coldeflists = lappend(coldeflists, coldeflist);
581  }
582  continue; /* done with this function item */
583  }
584  }
585 
586  /* normal case ... */
587  last_srf = pstate->p_last_srf;
588 
589  newfexpr = transformExpr(pstate, fexpr,
591 
592  /* nodeFunctionscan.c requires SRFs to be at top level */
593  if (pstate->p_last_srf != last_srf &&
594  pstate->p_last_srf != newfexpr)
595  ereport(ERROR,
596  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
597  errmsg("set-returning functions must appear at top level of FROM"),
598  parser_errposition(pstate,
599  exprLocation(pstate->p_last_srf))));
600 
601  funcexprs = lappend(funcexprs, newfexpr);
602 
603  funcnames = lappend(funcnames,
604  FigureColname(fexpr));
605 
606  if (coldeflist && r->coldeflist)
607  ereport(ERROR,
608  (errcode(ERRCODE_SYNTAX_ERROR),
609  errmsg("multiple column definition lists are not allowed for the same function"),
610  parser_errposition(pstate,
611  exprLocation((Node *) r->coldeflist))));
612 
613  coldeflists = lappend(coldeflists, coldeflist);
614  }
615 
616  pstate->p_lateral_active = false;
617 
618  /*
619  * We must assign collations now so that the RTE exposes correct collation
620  * info for Vars created from it.
621  */
622  assign_list_collations(pstate, funcexprs);
623 
624  /*
625  * Install the top-level coldeflist if there was one (we already checked
626  * that there was no conflicting per-function coldeflist).
627  *
628  * We only allow this when there's a single function (even after UNNEST
629  * expansion) and no WITH ORDINALITY. The reason for the latter
630  * restriction is that it's not real clear whether the ordinality column
631  * should be in the coldeflist, and users are too likely to make mistakes
632  * in one direction or the other. Putting the coldeflist inside ROWS
633  * FROM() is much clearer in this case.
634  */
635  if (r->coldeflist)
636  {
637  if (list_length(funcexprs) != 1)
638  {
639  if (r->is_rowsfrom)
640  ereport(ERROR,
641  (errcode(ERRCODE_SYNTAX_ERROR),
642  errmsg("ROWS FROM() with multiple functions cannot have a column definition list"),
643  errhint("Put a separate column definition list for each function inside ROWS FROM()."),
644  parser_errposition(pstate,
645  exprLocation((Node *) r->coldeflist))));
646  else
647  ereport(ERROR,
648  (errcode(ERRCODE_SYNTAX_ERROR),
649  errmsg("UNNEST() with multiple arguments cannot have a column definition list"),
650  errhint("Use separate UNNEST() calls inside ROWS FROM(), and attach a column definition list to each one."),
651  parser_errposition(pstate,
652  exprLocation((Node *) r->coldeflist))));
653  }
654  if (r->ordinality)
655  ereport(ERROR,
656  (errcode(ERRCODE_SYNTAX_ERROR),
657  errmsg("WITH ORDINALITY cannot be used with a column definition list"),
658  errhint("Put the column definition list inside ROWS FROM()."),
659  parser_errposition(pstate,
660  exprLocation((Node *) r->coldeflist))));
661 
662  coldeflists = list_make1(r->coldeflist);
663  }
664 
665  /*
666  * Mark the RTE as LATERAL if the user said LATERAL explicitly, or if
667  * there are any lateral cross-references in it.
668  */
669  is_lateral = r->lateral || contain_vars_of_level((Node *) funcexprs, 0);
670 
671  /*
672  * OK, build an RTE and nsitem for the function.
673  */
674  return addRangeTableEntryForFunction(pstate,
675  funcnames, funcexprs, coldeflists,
676  r, is_lateral, true);
677 }
678 
679 /*
680  * transformRangeTableFunc -
681  * Transform a raw RangeTableFunc into TableFunc.
682  *
683  * Transform the namespace clauses, the document-generating expression, the
684  * row-generating expression, the column-generating expressions, and the
685  * default value expressions.
686  */
687 static ParseNamespaceItem *
689 {
691  const char *constructName;
692  Oid docType;
693  bool is_lateral;
694  ListCell *col;
695  char **names;
696  int colno;
697 
698  /*
699  * Currently we only support XMLTABLE here. See transformJsonTable() for
700  * JSON_TABLE support.
701  */
702  tf->functype = TFT_XMLTABLE;
703  constructName = "XMLTABLE";
704  docType = XMLOID;
705 
706  /*
707  * We make lateral_only names of this level visible, whether or not the
708  * RangeTableFunc is explicitly marked LATERAL. This is needed for SQL
709  * spec compliance and seems useful on convenience grounds for all
710  * functions in FROM.
711  *
712  * (LATERAL can't nest within a single pstate level, so we don't need
713  * save/restore logic here.)
714  */
715  Assert(!pstate->p_lateral_active);
716  pstate->p_lateral_active = true;
717 
718  /* Transform and apply typecast to the row-generating expression ... */
719  Assert(rtf->rowexpr != NULL);
720  tf->rowexpr = coerce_to_specific_type(pstate,
722  TEXTOID,
723  constructName);
724  assign_expr_collations(pstate, tf->rowexpr);
725 
726  /* ... and to the document itself */
727  Assert(rtf->docexpr != NULL);
728  tf->docexpr = coerce_to_specific_type(pstate,
730  docType,
731  constructName);
732  assign_expr_collations(pstate, tf->docexpr);
733 
734  /* undef ordinality column number */
735  tf->ordinalitycol = -1;
736 
737  /* Process column specs */
738  names = palloc(sizeof(char *) * list_length(rtf->columns));
739 
740  colno = 0;
741  foreach(col, rtf->columns)
742  {
743  RangeTableFuncCol *rawc = (RangeTableFuncCol *) lfirst(col);
744  Oid typid;
745  int32 typmod;
746  Node *colexpr;
747  Node *coldefexpr;
748  int j;
749 
750  tf->colnames = lappend(tf->colnames,
751  makeString(pstrdup(rawc->colname)));
752 
753  /*
754  * Determine the type and typmod for the new column. FOR ORDINALITY
755  * columns are INTEGER per spec; the others are user-specified.
756  */
757  if (rawc->for_ordinality)
758  {
759  if (tf->ordinalitycol != -1)
760  ereport(ERROR,
761  (errcode(ERRCODE_SYNTAX_ERROR),
762  errmsg("only one FOR ORDINALITY column is allowed"),
763  parser_errposition(pstate, rawc->location)));
764 
765  typid = INT4OID;
766  typmod = -1;
767  tf->ordinalitycol = colno;
768  }
769  else
770  {
771  if (rawc->typeName->setof)
772  ereport(ERROR,
773  (errcode(ERRCODE_INVALID_TABLE_DEFINITION),
774  errmsg("column \"%s\" cannot be declared SETOF",
775  rawc->colname),
776  parser_errposition(pstate, rawc->location)));
777 
778  typenameTypeIdAndMod(pstate, rawc->typeName,
779  &typid, &typmod);
780  }
781 
782  tf->coltypes = lappend_oid(tf->coltypes, typid);
783  tf->coltypmods = lappend_int(tf->coltypmods, typmod);
784  tf->colcollations = lappend_oid(tf->colcollations,
785  get_typcollation(typid));
786 
787  /* Transform the PATH and DEFAULT expressions */
788  if (rawc->colexpr)
789  {
790  colexpr = coerce_to_specific_type(pstate,
791  transformExpr(pstate, rawc->colexpr,
793  TEXTOID,
794  constructName);
795  assign_expr_collations(pstate, colexpr);
796  }
797  else
798  colexpr = NULL;
799 
800  if (rawc->coldefexpr)
801  {
802  coldefexpr = coerce_to_specific_type_typmod(pstate,
803  transformExpr(pstate, rawc->coldefexpr,
805  typid, typmod,
806  constructName);
807  assign_expr_collations(pstate, coldefexpr);
808  }
809  else
810  coldefexpr = NULL;
811 
812  tf->colexprs = lappend(tf->colexprs, colexpr);
813  tf->coldefexprs = lappend(tf->coldefexprs, coldefexpr);
814 
815  if (rawc->is_not_null)
816  tf->notnulls = bms_add_member(tf->notnulls, colno);
817 
818  /* make sure column names are unique */
819  for (j = 0; j < colno; j++)
820  if (strcmp(names[j], rawc->colname) == 0)
821  ereport(ERROR,
822  (errcode(ERRCODE_SYNTAX_ERROR),
823  errmsg("column name \"%s\" is not unique",
824  rawc->colname),
825  parser_errposition(pstate, rawc->location)));
826  names[colno] = rawc->colname;
827 
828  colno++;
829  }
830  pfree(names);
831 
832  /* Namespaces, if any, also need to be transformed */
833  if (rtf->namespaces != NIL)
834  {
835  ListCell *ns;
836  ListCell *lc2;
837  List *ns_uris = NIL;
838  List *ns_names = NIL;
839  bool default_ns_seen = false;
840 
841  foreach(ns, rtf->namespaces)
842  {
843  ResTarget *r = (ResTarget *) lfirst(ns);
844  Node *ns_uri;
845 
846  Assert(IsA(r, ResTarget));
847  ns_uri = transformExpr(pstate, r->val, EXPR_KIND_FROM_FUNCTION);
848  ns_uri = coerce_to_specific_type(pstate, ns_uri,
849  TEXTOID, constructName);
850  assign_expr_collations(pstate, ns_uri);
851  ns_uris = lappend(ns_uris, ns_uri);
852 
853  /* Verify consistency of name list: no dupes, only one DEFAULT */
854  if (r->name != NULL)
855  {
856  foreach(lc2, ns_names)
857  {
858  String *ns_node = lfirst_node(String, lc2);
859 
860  if (ns_node == NULL)
861  continue;
862  if (strcmp(strVal(ns_node), r->name) == 0)
863  ereport(ERROR,
864  (errcode(ERRCODE_SYNTAX_ERROR),
865  errmsg("namespace name \"%s\" is not unique",
866  r->name),
867  parser_errposition(pstate, r->location)));
868  }
869  }
870  else
871  {
872  if (default_ns_seen)
873  ereport(ERROR,
874  (errcode(ERRCODE_SYNTAX_ERROR),
875  errmsg("only one default namespace is allowed"),
876  parser_errposition(pstate, r->location)));
877  default_ns_seen = true;
878  }
879 
880  /* We represent DEFAULT by a null pointer */
881  ns_names = lappend(ns_names,
882  r->name ? makeString(r->name) : NULL);
883  }
884 
885  tf->ns_uris = ns_uris;
886  tf->ns_names = ns_names;
887  }
888 
889  tf->location = rtf->location;
890 
891  pstate->p_lateral_active = false;
892 
893  /*
894  * Mark the RTE as LATERAL if the user said LATERAL explicitly, or if
895  * there are any lateral cross-references in it.
896  */
897  is_lateral = rtf->lateral || contain_vars_of_level((Node *) tf, 0);
898 
899  return addRangeTableEntryForTableFunc(pstate,
900  tf, rtf->alias, is_lateral, true);
901 }
902 
903 /*
904  * transformRangeTableSample --- transform a TABLESAMPLE clause
905  *
906  * Caller has already transformed rts->relation, we just have to validate
907  * the remaining fields and create a TableSampleClause node.
908  */
909 static TableSampleClause *
911 {
912  TableSampleClause *tablesample;
913  Oid handlerOid;
914  Oid funcargtypes[1];
915  TsmRoutine *tsm;
916  List *fargs;
917  ListCell *larg,
918  *ltyp;
919 
920  /*
921  * To validate the sample method name, look up the handler function, which
922  * has the same name, one dummy INTERNAL argument, and a result type of
923  * tsm_handler. (Note: tablesample method names are not schema-qualified
924  * in the SQL standard; but since they are just functions to us, we allow
925  * schema qualification to resolve any potential ambiguity.)
926  */
927  funcargtypes[0] = INTERNALOID;
928 
929  handlerOid = LookupFuncName(rts->method, 1, funcargtypes, true);
930 
931  /* we want error to complain about no-such-method, not no-such-function */
932  if (!OidIsValid(handlerOid))
933  ereport(ERROR,
934  (errcode(ERRCODE_UNDEFINED_OBJECT),
935  errmsg("tablesample method %s does not exist",
936  NameListToString(rts->method)),
937  parser_errposition(pstate, rts->location)));
938 
939  /* check that handler has correct return type */
940  if (get_func_rettype(handlerOid) != TSM_HANDLEROID)
941  ereport(ERROR,
942  (errcode(ERRCODE_WRONG_OBJECT_TYPE),
943  errmsg("function %s must return type %s",
944  NameListToString(rts->method), "tsm_handler"),
945  parser_errposition(pstate, rts->location)));
946 
947  /* OK, run the handler to get TsmRoutine, for argument type info */
948  tsm = GetTsmRoutine(handlerOid);
949 
950  tablesample = makeNode(TableSampleClause);
951  tablesample->tsmhandler = handlerOid;
952 
953  /* check user provided the expected number of arguments */
954  if (list_length(rts->args) != list_length(tsm->parameterTypes))
955  ereport(ERROR,
956  (errcode(ERRCODE_INVALID_TABLESAMPLE_ARGUMENT),
957  errmsg_plural("tablesample method %s requires %d argument, not %d",
958  "tablesample method %s requires %d arguments, not %d",
960  NameListToString(rts->method),
962  list_length(rts->args)),
963  parser_errposition(pstate, rts->location)));
964 
965  /*
966  * Transform the arguments, typecasting them as needed. Note we must also
967  * assign collations now, because assign_query_collations() doesn't
968  * examine any substructure of RTEs.
969  */
970  fargs = NIL;
971  forboth(larg, rts->args, ltyp, tsm->parameterTypes)
972  {
973  Node *arg = (Node *) lfirst(larg);
974  Oid argtype = lfirst_oid(ltyp);
975 
977  arg = coerce_to_specific_type(pstate, arg, argtype, "TABLESAMPLE");
978  assign_expr_collations(pstate, arg);
979  fargs = lappend(fargs, arg);
980  }
981  tablesample->args = fargs;
982 
983  /* Process REPEATABLE (seed) */
984  if (rts->repeatable != NULL)
985  {
986  Node *arg;
987 
988  if (!tsm->repeatable_across_queries)
989  ereport(ERROR,
990  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
991  errmsg("tablesample method %s does not support REPEATABLE",
992  NameListToString(rts->method)),
993  parser_errposition(pstate, rts->location)));
994 
996  arg = coerce_to_specific_type(pstate, arg, FLOAT8OID, "REPEATABLE");
997  assign_expr_collations(pstate, arg);
998  tablesample->repeatable = (Expr *) arg;
999  }
1000  else
1001  tablesample->repeatable = NULL;
1002 
1003  return tablesample;
1004 }
1005 
1006 /*
1007  * getNSItemForSpecialRelationTypes
1008  *
1009  * If given RangeVar refers to a CTE or an EphemeralNamedRelation,
1010  * build and return an appropriate ParseNamespaceItem, otherwise return NULL
1011  */
1012 static ParseNamespaceItem *
1014 {
1015  ParseNamespaceItem *nsitem;
1016  CommonTableExpr *cte;
1017  Index levelsup;
1018 
1019  /*
1020  * if it is a qualified name, it can't be a CTE or tuplestore reference
1021  */
1022  if (rv->schemaname)
1023  return NULL;
1024 
1025  cte = scanNameSpaceForCTE(pstate, rv->relname, &levelsup);
1026  if (cte)
1027  nsitem = addRangeTableEntryForCTE(pstate, cte, levelsup, rv, true);
1028  else if (scanNameSpaceForENR(pstate, rv->relname))
1029  nsitem = addRangeTableEntryForENR(pstate, rv, true);
1030  else
1031  nsitem = NULL;
1032 
1033  return nsitem;
1034 }
1035 
1036 /*
1037  * transformFromClauseItem -
1038  * Transform a FROM-clause item, adding any required entries to the
1039  * range table list being built in the ParseState, and return the
1040  * transformed item ready to include in the joinlist. Also build a
1041  * ParseNamespaceItem list describing the names exposed by this item.
1042  * This routine can recurse to handle SQL92 JOIN expressions.
1043  *
1044  * The function return value is the node to add to the jointree (a
1045  * RangeTblRef or JoinExpr). Additional output parameters are:
1046  *
1047  * *top_nsitem: receives the ParseNamespaceItem directly corresponding to the
1048  * jointree item. (This is only used during internal recursion, not by
1049  * outside callers.)
1050  *
1051  * *namespace: receives a List of ParseNamespaceItems for the RTEs exposed
1052  * as table/column names by this item. (The lateral_only flags in these items
1053  * are indeterminate and should be explicitly set by the caller before use.)
1054  */
1055 static Node *
1057  ParseNamespaceItem **top_nsitem,
1058  List **namespace)
1059 {
1060  /* Guard against stack overflow due to overly deep subtree */
1062 
1063  if (IsA(n, RangeVar))
1064  {
1065  /* Plain relation reference, or perhaps a CTE reference */
1066  RangeVar *rv = (RangeVar *) n;
1067  RangeTblRef *rtr;
1068  ParseNamespaceItem *nsitem;
1069 
1070  /* Check if it's a CTE or tuplestore reference */
1071  nsitem = getNSItemForSpecialRelationTypes(pstate, rv);
1072 
1073  /* if not found above, must be a table reference */
1074  if (!nsitem)
1075  nsitem = transformTableEntry(pstate, rv);
1076 
1077  *top_nsitem = nsitem;
1078  *namespace = list_make1(nsitem);
1079  rtr = makeNode(RangeTblRef);
1080  rtr->rtindex = nsitem->p_rtindex;
1081  return (Node *) rtr;
1082  }
1083  else if (IsA(n, RangeSubselect))
1084  {
1085  /* sub-SELECT is like a plain relation */
1086  RangeTblRef *rtr;
1087  ParseNamespaceItem *nsitem;
1088 
1089  nsitem = transformRangeSubselect(pstate, (RangeSubselect *) n);
1090  *top_nsitem = nsitem;
1091  *namespace = list_make1(nsitem);
1092  rtr = makeNode(RangeTblRef);
1093  rtr->rtindex = nsitem->p_rtindex;
1094  return (Node *) rtr;
1095  }
1096  else if (IsA(n, RangeFunction))
1097  {
1098  /* function is like a plain relation */
1099  RangeTblRef *rtr;
1100  ParseNamespaceItem *nsitem;
1101 
1102  nsitem = transformRangeFunction(pstate, (RangeFunction *) n);
1103  *top_nsitem = nsitem;
1104  *namespace = list_make1(nsitem);
1105  rtr = makeNode(RangeTblRef);
1106  rtr->rtindex = nsitem->p_rtindex;
1107  return (Node *) rtr;
1108  }
1109  else if (IsA(n, RangeTableFunc) || IsA(n, JsonTable))
1110  {
1111  /* table function is like a plain relation */
1112  RangeTblRef *rtr;
1113  ParseNamespaceItem *nsitem;
1114 
1115  if (IsA(n, JsonTable))
1116  nsitem = transformJsonTable(pstate, (JsonTable *) n);
1117  else
1118  nsitem = transformRangeTableFunc(pstate, (RangeTableFunc *) n);
1119 
1120  *top_nsitem = nsitem;
1121  *namespace = list_make1(nsitem);
1122  rtr = makeNode(RangeTblRef);
1123  rtr->rtindex = nsitem->p_rtindex;
1124  return (Node *) rtr;
1125  }
1126  else if (IsA(n, RangeTableSample))
1127  {
1128  /* TABLESAMPLE clause (wrapping some other valid FROM node) */
1129  RangeTableSample *rts = (RangeTableSample *) n;
1130  Node *rel;
1131  RangeTblEntry *rte;
1132 
1133  /* Recursively transform the contained relation */
1134  rel = transformFromClauseItem(pstate, rts->relation,
1135  top_nsitem, namespace);
1136  rte = (*top_nsitem)->p_rte;
1137  /* We only support this on plain relations and matviews */
1138  if (rte->rtekind != RTE_RELATION ||
1139  (rte->relkind != RELKIND_RELATION &&
1140  rte->relkind != RELKIND_MATVIEW &&
1141  rte->relkind != RELKIND_PARTITIONED_TABLE))
1142  ereport(ERROR,
1143  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1144  errmsg("TABLESAMPLE clause can only be applied to tables and materialized views"),
1145  parser_errposition(pstate, exprLocation(rts->relation))));
1146 
1147  /* Transform TABLESAMPLE details and attach to the RTE */
1148  rte->tablesample = transformRangeTableSample(pstate, rts);
1149  return rel;
1150  }
1151  else if (IsA(n, JoinExpr))
1152  {
1153  /* A newfangled join expression */
1154  JoinExpr *j = (JoinExpr *) n;
1155  ParseNamespaceItem *nsitem;
1156  ParseNamespaceItem *l_nsitem;
1157  ParseNamespaceItem *r_nsitem;
1158  List *l_namespace,
1159  *r_namespace,
1160  *my_namespace,
1161  *l_colnames,
1162  *r_colnames,
1163  *res_colnames,
1164  *l_colnos,
1165  *r_colnos,
1166  *res_colvars;
1167  ParseNamespaceColumn *l_nscolumns,
1168  *r_nscolumns,
1169  *res_nscolumns;
1170  int res_colindex;
1171  bool lateral_ok;
1172  int sv_namespace_length;
1173  int k;
1174 
1175  /*
1176  * Recursively process the left subtree, then the right. We must do
1177  * it in this order for correct visibility of LATERAL references.
1178  */
1179  j->larg = transformFromClauseItem(pstate, j->larg,
1180  &l_nsitem,
1181  &l_namespace);
1182 
1183  /*
1184  * Make the left-side RTEs available for LATERAL access within the
1185  * right side, by temporarily adding them to the pstate's namespace
1186  * list. Per SQL:2008, if the join type is not INNER or LEFT then the
1187  * left-side names must still be exposed, but it's an error to
1188  * reference them. (Stupid design, but that's what it says.) Hence,
1189  * we always push them into the namespace, but mark them as not
1190  * lateral_ok if the jointype is wrong.
1191  *
1192  * Notice that we don't require the merged namespace list to be
1193  * conflict-free. See the comments for scanNameSpaceForRefname().
1194  */
1195  lateral_ok = (j->jointype == JOIN_INNER || j->jointype == JOIN_LEFT);
1196  setNamespaceLateralState(l_namespace, true, lateral_ok);
1197 
1198  sv_namespace_length = list_length(pstate->p_namespace);
1199  pstate->p_namespace = list_concat(pstate->p_namespace, l_namespace);
1200 
1201  /* And now we can process the RHS */
1202  j->rarg = transformFromClauseItem(pstate, j->rarg,
1203  &r_nsitem,
1204  &r_namespace);
1205 
1206  /* Remove the left-side RTEs from the namespace list again */
1207  pstate->p_namespace = list_truncate(pstate->p_namespace,
1208  sv_namespace_length);
1209 
1210  /*
1211  * Check for conflicting refnames in left and right subtrees. Must do
1212  * this because higher levels will assume I hand back a self-
1213  * consistent namespace list.
1214  */
1215  checkNameSpaceConflicts(pstate, l_namespace, r_namespace);
1216 
1217  /*
1218  * Generate combined namespace info for possible use below.
1219  */
1220  my_namespace = list_concat(l_namespace, r_namespace);
1221 
1222  /*
1223  * We'll work from the nscolumns data and eref alias column names for
1224  * each of the input nsitems. Note that these include dropped
1225  * columns, which is helpful because we can keep track of physical
1226  * input column numbers more easily.
1227  */
1228  l_nscolumns = l_nsitem->p_nscolumns;
1229  l_colnames = l_nsitem->p_names->colnames;
1230  r_nscolumns = r_nsitem->p_nscolumns;
1231  r_colnames = r_nsitem->p_names->colnames;
1232 
1233  /*
1234  * Natural join does not explicitly specify columns; must generate
1235  * columns to join. Need to run through the list of columns from each
1236  * table or join result and match up the column names. Use the first
1237  * table, and check every column in the second table for a match.
1238  * (We'll check that the matches were unique later on.) The result of
1239  * this step is a list of column names just like an explicitly-written
1240  * USING list.
1241  */
1242  if (j->isNatural)
1243  {
1244  List *rlist = NIL;
1245  ListCell *lx,
1246  *rx;
1247 
1248  Assert(j->usingClause == NIL); /* shouldn't have USING() too */
1249 
1250  foreach(lx, l_colnames)
1251  {
1252  char *l_colname = strVal(lfirst(lx));
1253  String *m_name = NULL;
1254 
1255  if (l_colname[0] == '\0')
1256  continue; /* ignore dropped columns */
1257 
1258  foreach(rx, r_colnames)
1259  {
1260  char *r_colname = strVal(lfirst(rx));
1261 
1262  if (strcmp(l_colname, r_colname) == 0)
1263  {
1264  m_name = makeString(l_colname);
1265  break;
1266  }
1267  }
1268 
1269  /* matched a right column? then keep as join column... */
1270  if (m_name != NULL)
1271  rlist = lappend(rlist, m_name);
1272  }
1273 
1274  j->usingClause = rlist;
1275  }
1276 
1277  /*
1278  * If a USING clause alias was specified, save the USING columns as
1279  * its column list.
1280  */
1281  if (j->join_using_alias)
1282  j->join_using_alias->colnames = j->usingClause;
1283 
1284  /*
1285  * Now transform the join qualifications, if any.
1286  */
1287  l_colnos = NIL;
1288  r_colnos = NIL;
1289  res_colnames = NIL;
1290  res_colvars = NIL;
1291 
1292  /* this may be larger than needed, but it's not worth being exact */
1293  res_nscolumns = (ParseNamespaceColumn *)
1294  palloc0((list_length(l_colnames) + list_length(r_colnames)) *
1295  sizeof(ParseNamespaceColumn));
1296  res_colindex = 0;
1297 
1298  if (j->usingClause)
1299  {
1300  /*
1301  * JOIN/USING (or NATURAL JOIN, as transformed above). Transform
1302  * the list into an explicit ON-condition.
1303  */
1304  List *ucols = j->usingClause;
1305  List *l_usingvars = NIL;
1306  List *r_usingvars = NIL;
1307  ListCell *ucol;
1308 
1309  Assert(j->quals == NULL); /* shouldn't have ON() too */
1310 
1311  foreach(ucol, ucols)
1312  {
1313  char *u_colname = strVal(lfirst(ucol));
1314  ListCell *col;
1315  int ndx;
1316  int l_index = -1;
1317  int r_index = -1;
1318  Var *l_colvar,
1319  *r_colvar;
1320 
1321  Assert(u_colname[0] != '\0');
1322 
1323  /* Check for USING(foo,foo) */
1324  foreach(col, res_colnames)
1325  {
1326  char *res_colname = strVal(lfirst(col));
1327 
1328  if (strcmp(res_colname, u_colname) == 0)
1329  ereport(ERROR,
1330  (errcode(ERRCODE_DUPLICATE_COLUMN),
1331  errmsg("column name \"%s\" appears more than once in USING clause",
1332  u_colname)));
1333  }
1334 
1335  /* Find it in left input */
1336  ndx = 0;
1337  foreach(col, l_colnames)
1338  {
1339  char *l_colname = strVal(lfirst(col));
1340 
1341  if (strcmp(l_colname, u_colname) == 0)
1342  {
1343  if (l_index >= 0)
1344  ereport(ERROR,
1345  (errcode(ERRCODE_AMBIGUOUS_COLUMN),
1346  errmsg("common column name \"%s\" appears more than once in left table",
1347  u_colname)));
1348  l_index = ndx;
1349  }
1350  ndx++;
1351  }
1352  if (l_index < 0)
1353  ereport(ERROR,
1354  (errcode(ERRCODE_UNDEFINED_COLUMN),
1355  errmsg("column \"%s\" specified in USING clause does not exist in left table",
1356  u_colname)));
1357  l_colnos = lappend_int(l_colnos, l_index + 1);
1358 
1359  /* Find it in right input */
1360  ndx = 0;
1361  foreach(col, r_colnames)
1362  {
1363  char *r_colname = strVal(lfirst(col));
1364 
1365  if (strcmp(r_colname, u_colname) == 0)
1366  {
1367  if (r_index >= 0)
1368  ereport(ERROR,
1369  (errcode(ERRCODE_AMBIGUOUS_COLUMN),
1370  errmsg("common column name \"%s\" appears more than once in right table",
1371  u_colname)));
1372  r_index = ndx;
1373  }
1374  ndx++;
1375  }
1376  if (r_index < 0)
1377  ereport(ERROR,
1378  (errcode(ERRCODE_UNDEFINED_COLUMN),
1379  errmsg("column \"%s\" specified in USING clause does not exist in right table",
1380  u_colname)));
1381  r_colnos = lappend_int(r_colnos, r_index + 1);
1382 
1383  /* Build Vars to use in the generated JOIN ON clause */
1384  l_colvar = buildVarFromNSColumn(pstate, l_nscolumns + l_index);
1385  l_usingvars = lappend(l_usingvars, l_colvar);
1386  r_colvar = buildVarFromNSColumn(pstate, r_nscolumns + r_index);
1387  r_usingvars = lappend(r_usingvars, r_colvar);
1388 
1389  /*
1390  * While we're here, add column names to the res_colnames
1391  * list. It's a bit ugly to do this here while the
1392  * corresponding res_colvars entries are not made till later,
1393  * but doing this later would require an additional traversal
1394  * of the usingClause list.
1395  */
1396  res_colnames = lappend(res_colnames, lfirst(ucol));
1397  }
1398 
1399  /* Construct the generated JOIN ON clause */
1400  j->quals = transformJoinUsingClause(pstate,
1401  l_usingvars,
1402  r_usingvars);
1403  }
1404  else if (j->quals)
1405  {
1406  /* User-written ON-condition; transform it */
1407  j->quals = transformJoinOnClause(pstate, j, my_namespace);
1408  }
1409  else
1410  {
1411  /* CROSS JOIN: no quals */
1412  }
1413 
1414  /*
1415  * If this is an outer join, now mark the appropriate child RTEs as
1416  * being nulled by this join. We have finished processing the child
1417  * join expressions as well as the current join's quals, which deal in
1418  * non-nulled input columns. All future references to those RTEs will
1419  * see possibly-nulled values, and we should mark generated Vars to
1420  * account for that. In particular, the join alias Vars that we're
1421  * about to build should reflect the nulling effects of this join.
1422  *
1423  * A difficulty with doing this is that we need the join's RT index,
1424  * which we don't officially have yet. However, no other RTE can get
1425  * made between here and the addRangeTableEntryForJoin call, so we can
1426  * predict what the assignment will be. (Alternatively, we could call
1427  * addRangeTableEntryForJoin before we have all the data computed, but
1428  * this seems less ugly.)
1429  */
1430  j->rtindex = list_length(pstate->p_rtable) + 1;
1431 
1432  switch (j->jointype)
1433  {
1434  case JOIN_INNER:
1435  break;
1436  case JOIN_LEFT:
1437  markRelsAsNulledBy(pstate, j->rarg, j->rtindex);
1438  break;
1439  case JOIN_FULL:
1440  markRelsAsNulledBy(pstate, j->larg, j->rtindex);
1441  markRelsAsNulledBy(pstate, j->rarg, j->rtindex);
1442  break;
1443  case JOIN_RIGHT:
1444  markRelsAsNulledBy(pstate, j->larg, j->rtindex);
1445  break;
1446  default:
1447  /* shouldn't see any other types here */
1448  elog(ERROR, "unrecognized join type: %d",
1449  (int) j->jointype);
1450  break;
1451  }
1452 
1453  /*
1454  * Now we can construct join alias expressions for the USING columns.
1455  */
1456  if (j->usingClause)
1457  {
1458  ListCell *lc1,
1459  *lc2;
1460 
1461  /* Scan the colnos lists to recover info from the previous loop */
1462  forboth(lc1, l_colnos, lc2, r_colnos)
1463  {
1464  int l_index = lfirst_int(lc1) - 1;
1465  int r_index = lfirst_int(lc2) - 1;
1466  Var *l_colvar,
1467  *r_colvar;
1468  Node *u_colvar;
1469  ParseNamespaceColumn *res_nscolumn;
1470 
1471  /*
1472  * Note we re-build these Vars: they might have different
1473  * varnullingrels than the ones made in the previous loop.
1474  */
1475  l_colvar = buildVarFromNSColumn(pstate, l_nscolumns + l_index);
1476  r_colvar = buildVarFromNSColumn(pstate, r_nscolumns + r_index);
1477 
1478  /* Construct the join alias Var for this column */
1479  u_colvar = buildMergedJoinVar(pstate,
1480  j->jointype,
1481  l_colvar,
1482  r_colvar);
1483  res_colvars = lappend(res_colvars, u_colvar);
1484 
1485  /* Construct column's res_nscolumns[] entry */
1486  res_nscolumn = res_nscolumns + res_colindex;
1487  res_colindex++;
1488  if (u_colvar == (Node *) l_colvar)
1489  {
1490  /* Merged column is equivalent to left input */
1491  *res_nscolumn = l_nscolumns[l_index];
1492  }
1493  else if (u_colvar == (Node *) r_colvar)
1494  {
1495  /* Merged column is equivalent to right input */
1496  *res_nscolumn = r_nscolumns[r_index];
1497  }
1498  else
1499  {
1500  /*
1501  * Merged column is not semantically equivalent to either
1502  * input, so it needs to be referenced as the join output
1503  * column.
1504  */
1505  res_nscolumn->p_varno = j->rtindex;
1506  res_nscolumn->p_varattno = res_colindex;
1507  res_nscolumn->p_vartype = exprType(u_colvar);
1508  res_nscolumn->p_vartypmod = exprTypmod(u_colvar);
1509  res_nscolumn->p_varcollid = exprCollation(u_colvar);
1510  res_nscolumn->p_varnosyn = j->rtindex;
1511  res_nscolumn->p_varattnosyn = res_colindex;
1512  }
1513  }
1514  }
1515 
1516  /* Add remaining columns from each side to the output columns */
1517  res_colindex +=
1518  extractRemainingColumns(pstate,
1519  l_nscolumns, l_colnames, &l_colnos,
1520  &res_colnames, &res_colvars,
1521  res_nscolumns + res_colindex);
1522  res_colindex +=
1523  extractRemainingColumns(pstate,
1524  r_nscolumns, r_colnames, &r_colnos,
1525  &res_colnames, &res_colvars,
1526  res_nscolumns + res_colindex);
1527 
1528  /* If join has an alias, it syntactically hides all inputs */
1529  if (j->alias)
1530  {
1531  for (k = 0; k < res_colindex; k++)
1532  {
1533  ParseNamespaceColumn *nscol = res_nscolumns + k;
1534 
1535  nscol->p_varnosyn = j->rtindex;
1536  nscol->p_varattnosyn = k + 1;
1537  }
1538  }
1539 
1540  /*
1541  * Now build an RTE and nsitem for the result of the join.
1542  */
1543  nsitem = addRangeTableEntryForJoin(pstate,
1544  res_colnames,
1545  res_nscolumns,
1546  j->jointype,
1547  list_length(j->usingClause),
1548  res_colvars,
1549  l_colnos,
1550  r_colnos,
1551  j->join_using_alias,
1552  j->alias,
1553  true);
1554 
1555  /* Verify that we correctly predicted the join's RT index */
1556  Assert(j->rtindex == nsitem->p_rtindex);
1557  /* Cross-check number of columns, too */
1558  Assert(res_colindex == list_length(nsitem->p_names->colnames));
1559 
1560  /*
1561  * Save a link to the JoinExpr in the proper element of p_joinexprs.
1562  * Since we maintain that list lazily, it may be necessary to fill in
1563  * empty entries before we can add the JoinExpr in the right place.
1564  */
1565  for (k = list_length(pstate->p_joinexprs) + 1; k < j->rtindex; k++)
1566  pstate->p_joinexprs = lappend(pstate->p_joinexprs, NULL);
1567  pstate->p_joinexprs = lappend(pstate->p_joinexprs, j);
1568  Assert(list_length(pstate->p_joinexprs) == j->rtindex);
1569 
1570  /*
1571  * If the join has a USING alias, build a ParseNamespaceItem for that
1572  * and add it to the list of nsitems in the join's input.
1573  */
1574  if (j->join_using_alias)
1575  {
1576  ParseNamespaceItem *jnsitem;
1577 
1578  jnsitem = (ParseNamespaceItem *) palloc(sizeof(ParseNamespaceItem));
1579  jnsitem->p_names = j->join_using_alias;
1580  jnsitem->p_rte = nsitem->p_rte;
1581  jnsitem->p_rtindex = nsitem->p_rtindex;
1582  jnsitem->p_perminfo = NULL;
1583  /* no need to copy the first N columns, just use res_nscolumns */
1584  jnsitem->p_nscolumns = res_nscolumns;
1585  /* set default visibility flags; might get changed later */
1586  jnsitem->p_rel_visible = true;
1587  jnsitem->p_cols_visible = true;
1588  jnsitem->p_lateral_only = false;
1589  jnsitem->p_lateral_ok = true;
1590  /* Per SQL, we must check for alias conflicts */
1591  checkNameSpaceConflicts(pstate, list_make1(jnsitem), my_namespace);
1592  my_namespace = lappend(my_namespace, jnsitem);
1593  }
1594 
1595  /*
1596  * Prepare returned namespace list. If the JOIN has an alias then it
1597  * hides the contained RTEs completely; otherwise, the contained RTEs
1598  * are still visible as table names, but are not visible for
1599  * unqualified column-name access.
1600  *
1601  * Note: if there are nested alias-less JOINs, the lower-level ones
1602  * will remain in the list although they have neither p_rel_visible
1603  * nor p_cols_visible set. We could delete such list items, but it's
1604  * unclear that it's worth expending cycles to do so.
1605  */
1606  if (j->alias != NULL)
1607  my_namespace = NIL;
1608  else
1609  setNamespaceColumnVisibility(my_namespace, false);
1610 
1611  /*
1612  * The join RTE itself is always made visible for unqualified column
1613  * names. It's visible as a relation name only if it has an alias.
1614  */
1615  nsitem->p_rel_visible = (j->alias != NULL);
1616  nsitem->p_cols_visible = true;
1617  nsitem->p_lateral_only = false;
1618  nsitem->p_lateral_ok = true;
1619 
1620  *top_nsitem = nsitem;
1621  *namespace = lappend(my_namespace, nsitem);
1622 
1623  return (Node *) j;
1624  }
1625  else
1626  elog(ERROR, "unrecognized node type: %d", (int) nodeTag(n));
1627  return NULL; /* can't get here, keep compiler quiet */
1628 }
1629 
1630 /*
1631  * buildVarFromNSColumn -
1632  * build a Var node using ParseNamespaceColumn data
1633  *
1634  * This is used to construct joinaliasvars entries.
1635  * We can assume varlevelsup should be 0, and no location is specified.
1636  * Note also that no column SELECT privilege is requested here; that would
1637  * happen only if the column is actually referenced in the query.
1638  */
1639 static Var *
1641 {
1642  Var *var;
1643 
1644  Assert(nscol->p_varno > 0); /* i.e., not deleted column */
1645  var = makeVar(nscol->p_varno,
1646  nscol->p_varattno,
1647  nscol->p_vartype,
1648  nscol->p_vartypmod,
1649  nscol->p_varcollid,
1650  0);
1651  /* makeVar doesn't offer parameters for these, so set by hand: */
1652  var->varnosyn = nscol->p_varnosyn;
1653  var->varattnosyn = nscol->p_varattnosyn;
1654 
1655  /* ... and update varnullingrels */
1656  markNullableIfNeeded(pstate, var);
1657 
1658  return var;
1659 }
1660 
1661 /*
1662  * buildMergedJoinVar -
1663  * generate a suitable replacement expression for a merged join column
1664  */
1665 static Node *
1667  Var *l_colvar, Var *r_colvar)
1668 {
1669  Oid outcoltype;
1670  int32 outcoltypmod;
1671  Node *l_node,
1672  *r_node,
1673  *res_node;
1674 
1675  outcoltype = select_common_type(pstate,
1676  list_make2(l_colvar, r_colvar),
1677  "JOIN/USING",
1678  NULL);
1679  outcoltypmod = select_common_typmod(pstate,
1680  list_make2(l_colvar, r_colvar),
1681  outcoltype);
1682 
1683  /*
1684  * Insert coercion functions if needed. Note that a difference in typmod
1685  * can only happen if input has typmod but outcoltypmod is -1. In that
1686  * case we insert a RelabelType to clearly mark that result's typmod is
1687  * not same as input. We never need coerce_type_typmod.
1688  */
1689  if (l_colvar->vartype != outcoltype)
1690  l_node = coerce_type(pstate, (Node *) l_colvar, l_colvar->vartype,
1691  outcoltype, outcoltypmod,
1693  else if (l_colvar->vartypmod != outcoltypmod)
1694  l_node = (Node *) makeRelabelType((Expr *) l_colvar,
1695  outcoltype, outcoltypmod,
1696  InvalidOid, /* fixed below */
1698  else
1699  l_node = (Node *) l_colvar;
1700 
1701  if (r_colvar->vartype != outcoltype)
1702  r_node = coerce_type(pstate, (Node *) r_colvar, r_colvar->vartype,
1703  outcoltype, outcoltypmod,
1705  else if (r_colvar->vartypmod != outcoltypmod)
1706  r_node = (Node *) makeRelabelType((Expr *) r_colvar,
1707  outcoltype, outcoltypmod,
1708  InvalidOid, /* fixed below */
1710  else
1711  r_node = (Node *) r_colvar;
1712 
1713  /*
1714  * Choose what to emit
1715  */
1716  switch (jointype)
1717  {
1718  case JOIN_INNER:
1719 
1720  /*
1721  * We can use either var; prefer non-coerced one if available.
1722  */
1723  if (IsA(l_node, Var))
1724  res_node = l_node;
1725  else if (IsA(r_node, Var))
1726  res_node = r_node;
1727  else
1728  res_node = l_node;
1729  break;
1730  case JOIN_LEFT:
1731  /* Always use left var */
1732  res_node = l_node;
1733  break;
1734  case JOIN_RIGHT:
1735  /* Always use right var */
1736  res_node = r_node;
1737  break;
1738  case JOIN_FULL:
1739  {
1740  /*
1741  * Here we must build a COALESCE expression to ensure that the
1742  * join output is non-null if either input is.
1743  */
1745 
1746  c->coalescetype = outcoltype;
1747  /* coalescecollid will get set below */
1748  c->args = list_make2(l_node, r_node);
1749  c->location = -1;
1750  res_node = (Node *) c;
1751  break;
1752  }
1753  default:
1754  elog(ERROR, "unrecognized join type: %d", (int) jointype);
1755  res_node = NULL; /* keep compiler quiet */
1756  break;
1757  }
1758 
1759  /*
1760  * Apply assign_expr_collations to fix up the collation info in the
1761  * coercion and CoalesceExpr nodes, if we made any. This must be done now
1762  * so that the join node's alias vars show correct collation info.
1763  */
1764  assign_expr_collations(pstate, res_node);
1765 
1766  return res_node;
1767 }
1768 
1769 /*
1770  * markRelsAsNulledBy -
1771  * Mark the given jointree node and its children as nulled by join jindex
1772  */
1773 static void
1774 markRelsAsNulledBy(ParseState *pstate, Node *n, int jindex)
1775 {
1776  int varno;
1777  ListCell *lc;
1778 
1779  /* Note: we can't see FromExpr here */
1780  if (IsA(n, RangeTblRef))
1781  {
1782  varno = ((RangeTblRef *) n)->rtindex;
1783  }
1784  else if (IsA(n, JoinExpr))
1785  {
1786  JoinExpr *j = (JoinExpr *) n;
1787 
1788  /* recurse to children */
1789  markRelsAsNulledBy(pstate, j->larg, jindex);
1790  markRelsAsNulledBy(pstate, j->rarg, jindex);
1791  varno = j->rtindex;
1792  }
1793  else
1794  {
1795  elog(ERROR, "unrecognized node type: %d", (int) nodeTag(n));
1796  varno = 0; /* keep compiler quiet */
1797  }
1798 
1799  /*
1800  * Now add jindex to the p_nullingrels set for relation varno. Since we
1801  * maintain the p_nullingrels list lazily, we might need to extend it to
1802  * make the varno'th entry exist.
1803  */
1804  while (list_length(pstate->p_nullingrels) < varno)
1805  pstate->p_nullingrels = lappend(pstate->p_nullingrels, NULL);
1806  lc = list_nth_cell(pstate->p_nullingrels, varno - 1);
1807  lfirst(lc) = bms_add_member((Bitmapset *) lfirst(lc), jindex);
1808 }
1809 
1810 /*
1811  * setNamespaceColumnVisibility -
1812  * Convenience subroutine to update cols_visible flags in a namespace list.
1813  */
1814 static void
1815 setNamespaceColumnVisibility(List *namespace, bool cols_visible)
1816 {
1817  ListCell *lc;
1818 
1819  foreach(lc, namespace)
1820  {
1821  ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
1822 
1823  nsitem->p_cols_visible = cols_visible;
1824  }
1825 }
1826 
1827 /*
1828  * setNamespaceLateralState -
1829  * Convenience subroutine to update LATERAL flags in a namespace list.
1830  */
1831 static void
1832 setNamespaceLateralState(List *namespace, bool lateral_only, bool lateral_ok)
1833 {
1834  ListCell *lc;
1835 
1836  foreach(lc, namespace)
1837  {
1838  ParseNamespaceItem *nsitem = (ParseNamespaceItem *) lfirst(lc);
1839 
1840  nsitem->p_lateral_only = lateral_only;
1841  nsitem->p_lateral_ok = lateral_ok;
1842  }
1843 }
1844 
1845 
1846 /*
1847  * transformWhereClause -
1848  * Transform the qualification and make sure it is of type boolean.
1849  * Used for WHERE and allied clauses.
1850  *
1851  * constructName does not affect the semantics, but is used in error messages
1852  */
1853 Node *
1855  ParseExprKind exprKind, const char *constructName)
1856 {
1857  Node *qual;
1858 
1859  if (clause == NULL)
1860  return NULL;
1861 
1862  qual = transformExpr(pstate, clause, exprKind);
1863 
1864  qual = coerce_to_boolean(pstate, qual, constructName);
1865 
1866  return qual;
1867 }
1868 
1869 
1870 /*
1871  * transformLimitClause -
1872  * Transform the expression and make sure it is of type bigint.
1873  * Used for LIMIT and allied clauses.
1874  *
1875  * Note: as of Postgres 8.2, LIMIT expressions are expected to yield int8,
1876  * rather than int4 as before.
1877  *
1878  * constructName does not affect the semantics, but is used in error messages
1879  */
1880 Node *
1882  ParseExprKind exprKind, const char *constructName,
1883  LimitOption limitOption)
1884 {
1885  Node *qual;
1886 
1887  if (clause == NULL)
1888  return NULL;
1889 
1890  qual = transformExpr(pstate, clause, exprKind);
1891 
1892  qual = coerce_to_specific_type(pstate, qual, INT8OID, constructName);
1893 
1894  /* LIMIT can't refer to any variables of the current query */
1895  checkExprIsVarFree(pstate, qual, constructName);
1896 
1897  /*
1898  * Don't allow NULLs in FETCH FIRST .. WITH TIES. This test is ugly and
1899  * extremely simplistic, in that you can pass a NULL anyway by hiding it
1900  * inside an expression -- but this protects ruleutils against emitting an
1901  * unadorned NULL that's not accepted back by the grammar.
1902  */
1903  if (exprKind == EXPR_KIND_LIMIT && limitOption == LIMIT_OPTION_WITH_TIES &&
1904  IsA(clause, A_Const) && castNode(A_Const, clause)->isnull)
1905  ereport(ERROR,
1906  (errcode(ERRCODE_INVALID_ROW_COUNT_IN_LIMIT_CLAUSE),
1907  errmsg("row count cannot be null in FETCH FIRST ... WITH TIES clause")));
1908 
1909  return qual;
1910 }
1911 
1912 /*
1913  * checkExprIsVarFree
1914  * Check that given expr has no Vars of the current query level
1915  * (aggregates and window functions should have been rejected already).
1916  *
1917  * This is used to check expressions that have to have a consistent value
1918  * across all rows of the query, such as a LIMIT. Arguably it should reject
1919  * volatile functions, too, but we don't do that --- whatever value the
1920  * function gives on first execution is what you get.
1921  *
1922  * constructName does not affect the semantics, but is used in error messages
1923  */
1924 static void
1925 checkExprIsVarFree(ParseState *pstate, Node *n, const char *constructName)
1926 {
1927  if (contain_vars_of_level(n, 0))
1928  {
1929  ereport(ERROR,
1930  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
1931  /* translator: %s is name of a SQL construct, eg LIMIT */
1932  errmsg("argument of %s must not contain variables",
1933  constructName),
1934  parser_errposition(pstate,
1935  locate_var_of_level(n, 0))));
1936  }
1937 }
1938 
1939 
1940 /*
1941  * checkTargetlistEntrySQL92 -
1942  * Validate a targetlist entry found by findTargetlistEntrySQL92
1943  *
1944  * When we select a pre-existing tlist entry as a result of syntax such
1945  * as "GROUP BY 1", we have to make sure it is acceptable for use in the
1946  * indicated clause type; transformExpr() will have treated it as a regular
1947  * targetlist item.
1948  */
1949 static void
1951  ParseExprKind exprKind)
1952 {
1953  switch (exprKind)
1954  {
1955  case EXPR_KIND_GROUP_BY:
1956  /* reject aggregates and window functions */
1957  if (pstate->p_hasAggs &&
1958  contain_aggs_of_level((Node *) tle->expr, 0))
1959  ereport(ERROR,
1960  (errcode(ERRCODE_GROUPING_ERROR),
1961  /* translator: %s is name of a SQL construct, eg GROUP BY */
1962  errmsg("aggregate functions are not allowed in %s",
1963  ParseExprKindName(exprKind)),
1964  parser_errposition(pstate,
1965  locate_agg_of_level((Node *) tle->expr, 0))));
1966  if (pstate->p_hasWindowFuncs &&
1967  contain_windowfuncs((Node *) tle->expr))
1968  ereport(ERROR,
1969  (errcode(ERRCODE_WINDOWING_ERROR),
1970  /* translator: %s is name of a SQL construct, eg GROUP BY */
1971  errmsg("window functions are not allowed in %s",
1972  ParseExprKindName(exprKind)),
1973  parser_errposition(pstate,
1974  locate_windowfunc((Node *) tle->expr))));
1975  break;
1976  case EXPR_KIND_ORDER_BY:
1977  /* no extra checks needed */
1978  break;
1979  case EXPR_KIND_DISTINCT_ON:
1980  /* no extra checks needed */
1981  break;
1982  default:
1983  elog(ERROR, "unexpected exprKind in checkTargetlistEntrySQL92");
1984  break;
1985  }
1986 }
1987 
1988 /*
1989  * findTargetlistEntrySQL92 -
1990  * Returns the targetlist entry matching the given (untransformed) node.
1991  * If no matching entry exists, one is created and appended to the target
1992  * list as a "resjunk" node.
1993  *
1994  * This function supports the old SQL92 ORDER BY interpretation, where the
1995  * expression is an output column name or number. If we fail to find a
1996  * match of that sort, we fall through to the SQL99 rules. For historical
1997  * reasons, Postgres also allows this interpretation for GROUP BY, though
1998  * the standard never did. However, for GROUP BY we prefer a SQL99 match.
1999  * This function is *not* used for WINDOW definitions.
2000  *
2001  * node the ORDER BY, GROUP BY, or DISTINCT ON expression to be matched
2002  * tlist the target list (passed by reference so we can append to it)
2003  * exprKind identifies clause type being processed
2004  */
2005 static TargetEntry *
2007  ParseExprKind exprKind)
2008 {
2009  ListCell *tl;
2010 
2011  /*----------
2012  * Handle two special cases as mandated by the SQL92 spec:
2013  *
2014  * 1. Bare ColumnName (no qualifier or subscripts)
2015  * For a bare identifier, we search for a matching column name
2016  * in the existing target list. Multiple matches are an error
2017  * unless they refer to identical values; for example,
2018  * we allow SELECT a, a FROM table ORDER BY a
2019  * but not SELECT a AS b, b FROM table ORDER BY b
2020  * If no match is found, we fall through and treat the identifier
2021  * as an expression.
2022  * For GROUP BY, it is incorrect to match the grouping item against
2023  * targetlist entries: according to SQL92, an identifier in GROUP BY
2024  * is a reference to a column name exposed by FROM, not to a target
2025  * list column. However, many implementations (including pre-7.0
2026  * PostgreSQL) accept this anyway. So for GROUP BY, we look first
2027  * to see if the identifier matches any FROM column name, and only
2028  * try for a targetlist name if it doesn't. This ensures that we
2029  * adhere to the spec in the case where the name could be both.
2030  * DISTINCT ON isn't in the standard, so we can do what we like there;
2031  * we choose to make it work like ORDER BY, on the rather flimsy
2032  * grounds that ordinary DISTINCT works on targetlist entries.
2033  *
2034  * 2. IntegerConstant
2035  * This means to use the n'th item in the existing target list.
2036  * Note that it would make no sense to order/group/distinct by an
2037  * actual constant, so this does not create a conflict with SQL99.
2038  * GROUP BY column-number is not allowed by SQL92, but since
2039  * the standard has no other behavior defined for this syntax,
2040  * we may as well accept this common extension.
2041  *
2042  * Note that pre-existing resjunk targets must not be used in either case,
2043  * since the user didn't write them in his SELECT list.
2044  *
2045  * If neither special case applies, fall through to treat the item as
2046  * an expression per SQL99.
2047  *----------
2048  */
2049  if (IsA(node, ColumnRef) &&
2050  list_length(((ColumnRef *) node)->fields) == 1 &&
2051  IsA(linitial(((ColumnRef *) node)->fields), String))
2052  {
2053  char *name = strVal(linitial(((ColumnRef *) node)->fields));
2054  int location = ((ColumnRef *) node)->location;
2055 
2056  if (exprKind == EXPR_KIND_GROUP_BY)
2057  {
2058  /*
2059  * In GROUP BY, we must prefer a match against a FROM-clause
2060  * column to one against the targetlist. Look to see if there is
2061  * a matching column. If so, fall through to use SQL99 rules.
2062  * NOTE: if name could refer ambiguously to more than one column
2063  * name exposed by FROM, colNameToVar will ereport(ERROR). That's
2064  * just what we want here.
2065  *
2066  * Small tweak for 7.4.3: ignore matches in upper query levels.
2067  * This effectively changes the search order for bare names to (1)
2068  * local FROM variables, (2) local targetlist aliases, (3) outer
2069  * FROM variables, whereas before it was (1) (3) (2). SQL92 and
2070  * SQL99 do not allow GROUPing BY an outer reference, so this
2071  * breaks no cases that are legal per spec, and it seems a more
2072  * self-consistent behavior.
2073  */
2074  if (colNameToVar(pstate, name, true, location) != NULL)
2075  name = NULL;
2076  }
2077 
2078  if (name != NULL)
2079  {
2080  TargetEntry *target_result = NULL;
2081 
2082  foreach(tl, *tlist)
2083  {
2084  TargetEntry *tle = (TargetEntry *) lfirst(tl);
2085 
2086  if (!tle->resjunk &&
2087  strcmp(tle->resname, name) == 0)
2088  {
2089  if (target_result != NULL)
2090  {
2091  if (!equal(target_result->expr, tle->expr))
2092  ereport(ERROR,
2093  (errcode(ERRCODE_AMBIGUOUS_COLUMN),
2094 
2095  /*------
2096  translator: first %s is name of a SQL construct, eg ORDER BY */
2097  errmsg("%s \"%s\" is ambiguous",
2098  ParseExprKindName(exprKind),
2099  name),
2100  parser_errposition(pstate, location)));
2101  }
2102  else
2103  target_result = tle;
2104  /* Stay in loop to check for ambiguity */
2105  }
2106  }
2107  if (target_result != NULL)
2108  {
2109  /* return the first match, after suitable validation */
2110  checkTargetlistEntrySQL92(pstate, target_result, exprKind);
2111  return target_result;
2112  }
2113  }
2114  }
2115  if (IsA(node, A_Const))
2116  {
2117  A_Const *aconst = castNode(A_Const, node);
2118  int targetlist_pos = 0;
2119  int target_pos;
2120 
2121  if (!IsA(&aconst->val, Integer))
2122  ereport(ERROR,
2123  (errcode(ERRCODE_SYNTAX_ERROR),
2124  /* translator: %s is name of a SQL construct, eg ORDER BY */
2125  errmsg("non-integer constant in %s",
2126  ParseExprKindName(exprKind)),
2127  parser_errposition(pstate, aconst->location)));
2128 
2129  target_pos = intVal(&aconst->val);
2130  foreach(tl, *tlist)
2131  {
2132  TargetEntry *tle = (TargetEntry *) lfirst(tl);
2133 
2134  if (!tle->resjunk)
2135  {
2136  if (++targetlist_pos == target_pos)
2137  {
2138  /* return the unique match, after suitable validation */
2139  checkTargetlistEntrySQL92(pstate, tle, exprKind);
2140  return tle;
2141  }
2142  }
2143  }
2144  ereport(ERROR,
2145  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
2146  /* translator: %s is name of a SQL construct, eg ORDER BY */
2147  errmsg("%s position %d is not in select list",
2148  ParseExprKindName(exprKind), target_pos),
2149  parser_errposition(pstate, aconst->location)));
2150  }
2151 
2152  /*
2153  * Otherwise, we have an expression, so process it per SQL99 rules.
2154  */
2155  return findTargetlistEntrySQL99(pstate, node, tlist, exprKind);
2156 }
2157 
2158 /*
2159  * findTargetlistEntrySQL99 -
2160  * Returns the targetlist entry matching the given (untransformed) node.
2161  * If no matching entry exists, one is created and appended to the target
2162  * list as a "resjunk" node.
2163  *
2164  * This function supports the SQL99 interpretation, wherein the expression
2165  * is just an ordinary expression referencing input column names.
2166  *
2167  * node the ORDER BY, GROUP BY, etc expression to be matched
2168  * tlist the target list (passed by reference so we can append to it)
2169  * exprKind identifies clause type being processed
2170  */
2171 static TargetEntry *
2173  ParseExprKind exprKind)
2174 {
2175  TargetEntry *target_result;
2176  ListCell *tl;
2177  Node *expr;
2178 
2179  /*
2180  * Convert the untransformed node to a transformed expression, and search
2181  * for a match in the tlist. NOTE: it doesn't really matter whether there
2182  * is more than one match. Also, we are willing to match an existing
2183  * resjunk target here, though the SQL92 cases above must ignore resjunk
2184  * targets.
2185  */
2186  expr = transformExpr(pstate, node, exprKind);
2187 
2188  foreach(tl, *tlist)
2189  {
2190  TargetEntry *tle = (TargetEntry *) lfirst(tl);
2191  Node *texpr;
2192 
2193  /*
2194  * Ignore any implicit cast on the existing tlist expression.
2195  *
2196  * This essentially allows the ORDER/GROUP/etc item to adopt the same
2197  * datatype previously selected for a textually-equivalent tlist item.
2198  * There can't be any implicit cast at top level in an ordinary SELECT
2199  * tlist at this stage, but the case does arise with ORDER BY in an
2200  * aggregate function.
2201  */
2202  texpr = strip_implicit_coercions((Node *) tle->expr);
2203 
2204  if (equal(expr, texpr))
2205  return tle;
2206  }
2207 
2208  /*
2209  * If no matches, construct a new target entry which is appended to the
2210  * end of the target list. This target is given resjunk = true so that it
2211  * will not be projected into the final tuple.
2212  */
2213  target_result = transformTargetEntry(pstate, node, expr, exprKind,
2214  NULL, true);
2215 
2216  *tlist = lappend(*tlist, target_result);
2217 
2218  return target_result;
2219 }
2220 
2221 /*-------------------------------------------------------------------------
2222  * Flatten out parenthesized sublists in grouping lists, and some cases
2223  * of nested grouping sets.
2224  *
2225  * Inside a grouping set (ROLLUP, CUBE, or GROUPING SETS), we expect the
2226  * content to be nested no more than 2 deep: i.e. ROLLUP((a,b),(c,d)) is
2227  * ok, but ROLLUP((a,(b,c)),d) is flattened to ((a,b,c),d), which we then
2228  * (later) normalize to ((a,b,c),(d)).
2229  *
2230  * CUBE or ROLLUP can be nested inside GROUPING SETS (but not the reverse),
2231  * and we leave that alone if we find it. But if we see GROUPING SETS inside
2232  * GROUPING SETS, we can flatten and normalize as follows:
2233  * GROUPING SETS (a, (b,c), GROUPING SETS ((c,d),(e)), (f,g))
2234  * becomes
2235  * GROUPING SETS ((a), (b,c), (c,d), (e), (f,g))
2236  *
2237  * This is per the spec's syntax transformations, but these are the only such
2238  * transformations we do in parse analysis, so that queries retain the
2239  * originally specified grouping set syntax for CUBE and ROLLUP as much as
2240  * possible when deparsed. (Full expansion of the result into a list of
2241  * grouping sets is left to the planner.)
2242  *
2243  * When we're done, the resulting list should contain only these possible
2244  * elements:
2245  * - an expression
2246  * - a CUBE or ROLLUP with a list of expressions nested 2 deep
2247  * - a GROUPING SET containing any of:
2248  * - expression lists
2249  * - empty grouping sets
2250  * - CUBE or ROLLUP nodes with lists nested 2 deep
2251  * The return is a new list, but doesn't deep-copy the old nodes except for
2252  * GroupingSet nodes.
2253  *
2254  * As a side effect, flag whether the list has any GroupingSet nodes.
2255  *-------------------------------------------------------------------------
2256  */
2257 static Node *
2258 flatten_grouping_sets(Node *expr, bool toplevel, bool *hasGroupingSets)
2259 {
2260  /* just in case of pathological input */
2262 
2263  if (expr == (Node *) NIL)
2264  return (Node *) NIL;
2265 
2266  switch (expr->type)
2267  {
2268  case T_RowExpr:
2269  {
2270  RowExpr *r = (RowExpr *) expr;
2271 
2272  if (r->row_format == COERCE_IMPLICIT_CAST)
2273  return flatten_grouping_sets((Node *) r->args,
2274  false, NULL);
2275  }
2276  break;
2277  case T_GroupingSet:
2278  {
2279  GroupingSet *gset = (GroupingSet *) expr;
2280  ListCell *l2;
2281  List *result_set = NIL;
2282 
2283  if (hasGroupingSets)
2284  *hasGroupingSets = true;
2285 
2286  /*
2287  * at the top level, we skip over all empty grouping sets; the
2288  * caller can supply the canonical GROUP BY () if nothing is
2289  * left.
2290  */
2291 
2292  if (toplevel && gset->kind == GROUPING_SET_EMPTY)
2293  return (Node *) NIL;
2294 
2295  foreach(l2, gset->content)
2296  {
2297  Node *n1 = lfirst(l2);
2298  Node *n2 = flatten_grouping_sets(n1, false, NULL);
2299 
2300  if (IsA(n1, GroupingSet) &&
2301  ((GroupingSet *) n1)->kind == GROUPING_SET_SETS)
2302  result_set = list_concat(result_set, (List *) n2);
2303  else
2304  result_set = lappend(result_set, n2);
2305  }
2306 
2307  /*
2308  * At top level, keep the grouping set node; but if we're in a
2309  * nested grouping set, then we need to concat the flattened
2310  * result into the outer list if it's simply nested.
2311  */
2312 
2313  if (toplevel || (gset->kind != GROUPING_SET_SETS))
2314  {
2315  return (Node *) makeGroupingSet(gset->kind, result_set, gset->location);
2316  }
2317  else
2318  return (Node *) result_set;
2319  }
2320  case T_List:
2321  {
2322  List *result = NIL;
2323  ListCell *l;
2324 
2325  foreach(l, (List *) expr)
2326  {
2327  Node *n = flatten_grouping_sets(lfirst(l), toplevel, hasGroupingSets);
2328 
2329  if (n != (Node *) NIL)
2330  {
2331  if (IsA(n, List))
2332  result = list_concat(result, (List *) n);
2333  else
2334  result = lappend(result, n);
2335  }
2336  }
2337 
2338  return (Node *) result;
2339  }
2340  default:
2341  break;
2342  }
2343 
2344  return expr;
2345 }
2346 
2347 /*
2348  * Transform a single expression within a GROUP BY clause or grouping set.
2349  *
2350  * The expression is added to the targetlist if not already present, and to the
2351  * flatresult list (which will become the groupClause) if not already present
2352  * there. The sortClause is consulted for operator and sort order hints.
2353  *
2354  * Returns the ressortgroupref of the expression.
2355  *
2356  * flatresult reference to flat list of SortGroupClause nodes
2357  * seen_local bitmapset of sortgrouprefs already seen at the local level
2358  * pstate ParseState
2359  * gexpr node to transform
2360  * targetlist reference to TargetEntry list
2361  * sortClause ORDER BY clause (SortGroupClause nodes)
2362  * exprKind expression kind
2363  * useSQL99 SQL99 rather than SQL92 syntax
2364  * toplevel false if within any grouping set
2365  */
2366 static Index
2367 transformGroupClauseExpr(List **flatresult, Bitmapset *seen_local,
2368  ParseState *pstate, Node *gexpr,
2369  List **targetlist, List *sortClause,
2370  ParseExprKind exprKind, bool useSQL99, bool toplevel)
2371 {
2372  TargetEntry *tle;
2373  bool found = false;
2374 
2375  if (useSQL99)
2376  tle = findTargetlistEntrySQL99(pstate, gexpr,
2377  targetlist, exprKind);
2378  else
2379  tle = findTargetlistEntrySQL92(pstate, gexpr,
2380  targetlist, exprKind);
2381 
2382  if (tle->ressortgroupref > 0)
2383  {
2384  ListCell *sl;
2385 
2386  /*
2387  * Eliminate duplicates (GROUP BY x, x) but only at local level.
2388  * (Duplicates in grouping sets can affect the number of returned
2389  * rows, so can't be dropped indiscriminately.)
2390  *
2391  * Since we don't care about anything except the sortgroupref, we can
2392  * use a bitmapset rather than scanning lists.
2393  */
2394  if (bms_is_member(tle->ressortgroupref, seen_local))
2395  return 0;
2396 
2397  /*
2398  * If we're already in the flat clause list, we don't need to consider
2399  * adding ourselves again.
2400  */
2401  found = targetIsInSortList(tle, InvalidOid, *flatresult);
2402  if (found)
2403  return tle->ressortgroupref;
2404 
2405  /*
2406  * If the GROUP BY tlist entry also appears in ORDER BY, copy operator
2407  * info from the (first) matching ORDER BY item. This means that if
2408  * you write something like "GROUP BY foo ORDER BY foo USING <<<", the
2409  * GROUP BY operation silently takes on the equality semantics implied
2410  * by the ORDER BY. There are two reasons to do this: it improves the
2411  * odds that we can implement both GROUP BY and ORDER BY with a single
2412  * sort step, and it allows the user to choose the equality semantics
2413  * used by GROUP BY, should she be working with a datatype that has
2414  * more than one equality operator.
2415  *
2416  * If we're in a grouping set, though, we force our requested ordering
2417  * to be NULLS LAST, because if we have any hope of using a sorted agg
2418  * for the job, we're going to be tacking on generated NULL values
2419  * after the corresponding groups. If the user demands nulls first,
2420  * another sort step is going to be inevitable, but that's the
2421  * planner's problem.
2422  */
2423 
2424  foreach(sl, sortClause)
2425  {
2426  SortGroupClause *sc = (SortGroupClause *) lfirst(sl);
2427 
2428  if (sc->tleSortGroupRef == tle->ressortgroupref)
2429  {
2430  SortGroupClause *grpc = copyObject(sc);
2431 
2432  if (!toplevel)
2433  grpc->nulls_first = false;
2434  *flatresult = lappend(*flatresult, grpc);
2435  found = true;
2436  break;
2437  }
2438  }
2439  }
2440 
2441  /*
2442  * If no match in ORDER BY, just add it to the result using default
2443  * sort/group semantics.
2444  */
2445  if (!found)
2446  *flatresult = addTargetToGroupList(pstate, tle,
2447  *flatresult, *targetlist,
2448  exprLocation(gexpr));
2449 
2450  /*
2451  * _something_ must have assigned us a sortgroupref by now...
2452  */
2453 
2454  return tle->ressortgroupref;
2455 }
2456 
2457 /*
2458  * Transform a list of expressions within a GROUP BY clause or grouping set.
2459  *
2460  * The list of expressions belongs to a single clause within which duplicates
2461  * can be safely eliminated.
2462  *
2463  * Returns an integer list of ressortgroupref values.
2464  *
2465  * flatresult reference to flat list of SortGroupClause nodes
2466  * pstate ParseState
2467  * list nodes to transform
2468  * targetlist reference to TargetEntry list
2469  * sortClause ORDER BY clause (SortGroupClause nodes)
2470  * exprKind expression kind
2471  * useSQL99 SQL99 rather than SQL92 syntax
2472  * toplevel false if within any grouping set
2473  */
2474 static List *
2476  ParseState *pstate, List *list,
2477  List **targetlist, List *sortClause,
2478  ParseExprKind exprKind, bool useSQL99, bool toplevel)
2479 {
2480  Bitmapset *seen_local = NULL;
2481  List *result = NIL;
2482  ListCell *gl;
2483 
2484  foreach(gl, list)
2485  {
2486  Node *gexpr = (Node *) lfirst(gl);
2487 
2488  Index ref = transformGroupClauseExpr(flatresult,
2489  seen_local,
2490  pstate,
2491  gexpr,
2492  targetlist,
2493  sortClause,
2494  exprKind,
2495  useSQL99,
2496  toplevel);
2497 
2498  if (ref > 0)
2499  {
2500  seen_local = bms_add_member(seen_local, ref);
2501  result = lappend_int(result, ref);
2502  }
2503  }
2504 
2505  return result;
2506 }
2507 
2508 /*
2509  * Transform a grouping set and (recursively) its content.
2510  *
2511  * The grouping set might be a GROUPING SETS node with other grouping sets
2512  * inside it, but SETS within SETS have already been flattened out before
2513  * reaching here.
2514  *
2515  * Returns the transformed node, which now contains SIMPLE nodes with lists
2516  * of ressortgrouprefs rather than expressions.
2517  *
2518  * flatresult reference to flat list of SortGroupClause nodes
2519  * pstate ParseState
2520  * gset grouping set to transform
2521  * targetlist reference to TargetEntry list
2522  * sortClause ORDER BY clause (SortGroupClause nodes)
2523  * exprKind expression kind
2524  * useSQL99 SQL99 rather than SQL92 syntax
2525  * toplevel false if within any grouping set
2526  */
2527 static Node *
2529  ParseState *pstate, GroupingSet *gset,
2530  List **targetlist, List *sortClause,
2531  ParseExprKind exprKind, bool useSQL99, bool toplevel)
2532 {
2533  ListCell *gl;
2534  List *content = NIL;
2535 
2536  Assert(toplevel || gset->kind != GROUPING_SET_SETS);
2537 
2538  foreach(gl, gset->content)
2539  {
2540  Node *n = lfirst(gl);
2541 
2542  if (IsA(n, List))
2543  {
2544  List *l = transformGroupClauseList(flatresult,
2545  pstate, (List *) n,
2546  targetlist, sortClause,
2547  exprKind, useSQL99, false);
2548 
2549  content = lappend(content, makeGroupingSet(GROUPING_SET_SIMPLE,
2550  l,
2551  exprLocation(n)));
2552  }
2553  else if (IsA(n, GroupingSet))
2554  {
2555  GroupingSet *gset2 = (GroupingSet *) lfirst(gl);
2556 
2557  content = lappend(content, transformGroupingSet(flatresult,
2558  pstate, gset2,
2559  targetlist, sortClause,
2560  exprKind, useSQL99, false));
2561  }
2562  else
2563  {
2564  Index ref = transformGroupClauseExpr(flatresult,
2565  NULL,
2566  pstate,
2567  n,
2568  targetlist,
2569  sortClause,
2570  exprKind,
2571  useSQL99,
2572  false);
2573 
2574  content = lappend(content, makeGroupingSet(GROUPING_SET_SIMPLE,
2575  list_make1_int(ref),
2576  exprLocation(n)));
2577  }
2578  }
2579 
2580  /* Arbitrarily cap the size of CUBE, which has exponential growth */
2581  if (gset->kind == GROUPING_SET_CUBE)
2582  {
2583  if (list_length(content) > 12)
2584  ereport(ERROR,
2585  (errcode(ERRCODE_TOO_MANY_COLUMNS),
2586  errmsg("CUBE is limited to 12 elements"),
2587  parser_errposition(pstate, gset->location)));
2588  }
2589 
2590  return (Node *) makeGroupingSet(gset->kind, content, gset->location);
2591 }
2592 
2593 
2594 /*
2595  * transformGroupClause -
2596  * transform a GROUP BY clause
2597  *
2598  * GROUP BY items will be added to the targetlist (as resjunk columns)
2599  * if not already present, so the targetlist must be passed by reference.
2600  *
2601  * This is also used for window PARTITION BY clauses (which act almost the
2602  * same, but are always interpreted per SQL99 rules).
2603  *
2604  * Grouping sets make this a lot more complex than it was. Our goal here is
2605  * twofold: we make a flat list of SortGroupClause nodes referencing each
2606  * distinct expression used for grouping, with those expressions added to the
2607  * targetlist if needed. At the same time, we build the groupingSets tree,
2608  * which stores only ressortgrouprefs as integer lists inside GroupingSet nodes
2609  * (possibly nested, but limited in depth: a GROUPING_SET_SETS node can contain
2610  * nested SIMPLE, CUBE or ROLLUP nodes, but not more sets - we flatten that
2611  * out; while CUBE and ROLLUP can contain only SIMPLE nodes).
2612  *
2613  * We skip much of the hard work if there are no grouping sets.
2614  *
2615  * One subtlety is that the groupClause list can end up empty while the
2616  * groupingSets list is not; this happens if there are only empty grouping
2617  * sets, or an explicit GROUP BY (). This has the same effect as specifying
2618  * aggregates or a HAVING clause with no GROUP BY; the output is one row per
2619  * grouping set even if the input is empty.
2620  *
2621  * Returns the transformed (flat) groupClause.
2622  *
2623  * pstate ParseState
2624  * grouplist clause to transform
2625  * groupingSets reference to list to contain the grouping set tree
2626  * targetlist reference to TargetEntry list
2627  * sortClause ORDER BY clause (SortGroupClause nodes)
2628  * exprKind expression kind
2629  * useSQL99 SQL99 rather than SQL92 syntax
2630  */
2631 List *
2632 transformGroupClause(ParseState *pstate, List *grouplist, List **groupingSets,
2633  List **targetlist, List *sortClause,
2634  ParseExprKind exprKind, bool useSQL99)
2635 {
2636  List *result = NIL;
2637  List *flat_grouplist;
2638  List *gsets = NIL;
2639  ListCell *gl;
2640  bool hasGroupingSets = false;
2641  Bitmapset *seen_local = NULL;
2642 
2643  /*
2644  * Recursively flatten implicit RowExprs. (Technically this is only needed
2645  * for GROUP BY, per the syntax rules for grouping sets, but we do it
2646  * anyway.)
2647  */
2648  flat_grouplist = (List *) flatten_grouping_sets((Node *) grouplist,
2649  true,
2650  &hasGroupingSets);
2651 
2652  /*
2653  * If the list is now empty, but hasGroupingSets is true, it's because we
2654  * elided redundant empty grouping sets. Restore a single empty grouping
2655  * set to leave a canonical form: GROUP BY ()
2656  */
2657 
2658  if (flat_grouplist == NIL && hasGroupingSets)
2659  {
2661  NIL,
2662  exprLocation((Node *) grouplist)));
2663  }
2664 
2665  foreach(gl, flat_grouplist)
2666  {
2667  Node *gexpr = (Node *) lfirst(gl);
2668 
2669  if (IsA(gexpr, GroupingSet))
2670  {
2671  GroupingSet *gset = (GroupingSet *) gexpr;
2672 
2673  switch (gset->kind)
2674  {
2675  case GROUPING_SET_EMPTY:
2676  gsets = lappend(gsets, gset);
2677  break;
2678  case GROUPING_SET_SIMPLE:
2679  /* can't happen */
2680  Assert(false);
2681  break;
2682  case GROUPING_SET_SETS:
2683  case GROUPING_SET_CUBE:
2684  case GROUPING_SET_ROLLUP:
2685  gsets = lappend(gsets,
2686  transformGroupingSet(&result,
2687  pstate, gset,
2688  targetlist, sortClause,
2689  exprKind, useSQL99, true));
2690  break;
2691  }
2692  }
2693  else
2694  {
2695  Index ref = transformGroupClauseExpr(&result, seen_local,
2696  pstate, gexpr,
2697  targetlist, sortClause,
2698  exprKind, useSQL99, true);
2699 
2700  if (ref > 0)
2701  {
2702  seen_local = bms_add_member(seen_local, ref);
2703  if (hasGroupingSets)
2704  gsets = lappend(gsets,
2706  list_make1_int(ref),
2707  exprLocation(gexpr)));
2708  }
2709  }
2710  }
2711 
2712  /* parser should prevent this */
2713  Assert(gsets == NIL || groupingSets != NULL);
2714 
2715  if (groupingSets)
2716  *groupingSets = gsets;
2717 
2718  return result;
2719 }
2720 
2721 /*
2722  * transformSortClause -
2723  * transform an ORDER BY clause
2724  *
2725  * ORDER BY items will be added to the targetlist (as resjunk columns)
2726  * if not already present, so the targetlist must be passed by reference.
2727  *
2728  * This is also used for window and aggregate ORDER BY clauses (which act
2729  * almost the same, but are always interpreted per SQL99 rules).
2730  */
2731 List *
2733  List *orderlist,
2734  List **targetlist,
2735  ParseExprKind exprKind,
2736  bool useSQL99)
2737 {
2738  List *sortlist = NIL;
2739  ListCell *olitem;
2740 
2741  foreach(olitem, orderlist)
2742  {
2743  SortBy *sortby = (SortBy *) lfirst(olitem);
2744  TargetEntry *tle;
2745 
2746  if (useSQL99)
2747  tle = findTargetlistEntrySQL99(pstate, sortby->node,
2748  targetlist, exprKind);
2749  else
2750  tle = findTargetlistEntrySQL92(pstate, sortby->node,
2751  targetlist, exprKind);
2752 
2753  sortlist = addTargetToSortList(pstate, tle,
2754  sortlist, *targetlist, sortby);
2755  }
2756 
2757  return sortlist;
2758 }
2759 
2760 /*
2761  * transformWindowDefinitions -
2762  * transform window definitions (WindowDef to WindowClause)
2763  */
2764 List *
2766  List *windowdefs,
2767  List **targetlist)
2768 {
2769  List *result = NIL;
2770  Index winref = 0;
2771  ListCell *lc;
2772 
2773  foreach(lc, windowdefs)
2774  {
2775  WindowDef *windef = (WindowDef *) lfirst(lc);
2776  WindowClause *refwc = NULL;
2777  List *partitionClause;
2778  List *orderClause;
2779  Oid rangeopfamily = InvalidOid;
2780  Oid rangeopcintype = InvalidOid;
2781  WindowClause *wc;
2782 
2783  winref++;
2784 
2785  /*
2786  * Check for duplicate window names.
2787  */
2788  if (windef->name &&
2789  findWindowClause(result, windef->name) != NULL)
2790  ereport(ERROR,
2791  (errcode(ERRCODE_WINDOWING_ERROR),
2792  errmsg("window \"%s\" is already defined", windef->name),
2793  parser_errposition(pstate, windef->location)));
2794 
2795  /*
2796  * If it references a previous window, look that up.
2797  */
2798  if (windef->refname)
2799  {
2800  refwc = findWindowClause(result, windef->refname);
2801  if (refwc == NULL)
2802  ereport(ERROR,
2803  (errcode(ERRCODE_UNDEFINED_OBJECT),
2804  errmsg("window \"%s\" does not exist",
2805  windef->refname),
2806  parser_errposition(pstate, windef->location)));
2807  }
2808 
2809  /*
2810  * Transform PARTITION and ORDER specs, if any. These are treated
2811  * almost exactly like top-level GROUP BY and ORDER BY clauses,
2812  * including the special handling of nondefault operator semantics.
2813  */
2814  orderClause = transformSortClause(pstate,
2815  windef->orderClause,
2816  targetlist,
2818  true /* force SQL99 rules */ );
2819  partitionClause = transformGroupClause(pstate,
2820  windef->partitionClause,
2821  NULL,
2822  targetlist,
2823  orderClause,
2825  true /* force SQL99 rules */ );
2826 
2827  /*
2828  * And prepare the new WindowClause.
2829  */
2830  wc = makeNode(WindowClause);
2831  wc->name = windef->name;
2832  wc->refname = windef->refname;
2833 
2834  /*
2835  * Per spec, a windowdef that references a previous one copies the
2836  * previous partition clause (and mustn't specify its own). It can
2837  * specify its own ordering clause, but only if the previous one had
2838  * none. It always specifies its own frame clause, and the previous
2839  * one must not have a frame clause. Yeah, it's bizarre that each of
2840  * these cases works differently, but SQL:2008 says so; see 7.11
2841  * <window clause> syntax rule 10 and general rule 1. The frame
2842  * clause rule is especially bizarre because it makes "OVER foo"
2843  * different from "OVER (foo)", and requires the latter to throw an
2844  * error if foo has a nondefault frame clause. Well, ours not to
2845  * reason why, but we do go out of our way to throw a useful error
2846  * message for such cases.
2847  */
2848  if (refwc)
2849  {
2850  if (partitionClause)
2851  ereport(ERROR,
2852  (errcode(ERRCODE_WINDOWING_ERROR),
2853  errmsg("cannot override PARTITION BY clause of window \"%s\"",
2854  windef->refname),
2855  parser_errposition(pstate, windef->location)));
2857  }
2858  else
2859  wc->partitionClause = partitionClause;
2860  if (refwc)
2861  {
2862  if (orderClause && refwc->orderClause)
2863  ereport(ERROR,
2864  (errcode(ERRCODE_WINDOWING_ERROR),
2865  errmsg("cannot override ORDER BY clause of window \"%s\"",
2866  windef->refname),
2867  parser_errposition(pstate, windef->location)));
2868  if (orderClause)
2869  {
2870  wc->orderClause = orderClause;
2871  wc->copiedOrder = false;
2872  }
2873  else
2874  {
2875  wc->orderClause = copyObject(refwc->orderClause);
2876  wc->copiedOrder = true;
2877  }
2878  }
2879  else
2880  {
2881  wc->orderClause = orderClause;
2882  wc->copiedOrder = false;
2883  }
2884  if (refwc && refwc->frameOptions != FRAMEOPTION_DEFAULTS)
2885  {
2886  /*
2887  * Use this message if this is a WINDOW clause, or if it's an OVER
2888  * clause that includes ORDER BY or framing clauses. (We already
2889  * rejected PARTITION BY above, so no need to check that.)
2890  */
2891  if (windef->name ||
2892  orderClause || windef->frameOptions != FRAMEOPTION_DEFAULTS)
2893  ereport(ERROR,
2894  (errcode(ERRCODE_WINDOWING_ERROR),
2895  errmsg("cannot copy window \"%s\" because it has a frame clause",
2896  windef->refname),
2897  parser_errposition(pstate, windef->location)));
2898  /* Else this clause is just OVER (foo), so say this: */
2899  ereport(ERROR,
2900  (errcode(ERRCODE_WINDOWING_ERROR),
2901  errmsg("cannot copy window \"%s\" because it has a frame clause",
2902  windef->refname),
2903  errhint("Omit the parentheses in this OVER clause."),
2904  parser_errposition(pstate, windef->location)));
2905  }
2906  wc->frameOptions = windef->frameOptions;
2907 
2908  /*
2909  * RANGE offset PRECEDING/FOLLOWING requires exactly one ORDER BY
2910  * column; check that and get its sort opfamily info.
2911  */
2912  if ((wc->frameOptions & FRAMEOPTION_RANGE) &&
2915  {
2916  SortGroupClause *sortcl;
2917  Node *sortkey;
2918  int16 rangestrategy;
2919 
2920  if (list_length(wc->orderClause) != 1)
2921  ereport(ERROR,
2922  (errcode(ERRCODE_WINDOWING_ERROR),
2923  errmsg("RANGE with offset PRECEDING/FOLLOWING requires exactly one ORDER BY column"),
2924  parser_errposition(pstate, windef->location)));
2925  sortcl = linitial_node(SortGroupClause, wc->orderClause);
2926  sortkey = get_sortgroupclause_expr(sortcl, *targetlist);
2927  /* Find the sort operator in pg_amop */
2928  if (!get_ordering_op_properties(sortcl->sortop,
2929  &rangeopfamily,
2930  &rangeopcintype,
2931  &rangestrategy))
2932  elog(ERROR, "operator %u is not a valid ordering operator",
2933  sortcl->sortop);
2934  /* Record properties of sort ordering */
2935  wc->inRangeColl = exprCollation(sortkey);
2936  wc->inRangeAsc = (rangestrategy == BTLessStrategyNumber);
2937  wc->inRangeNullsFirst = sortcl->nulls_first;
2938  }
2939 
2940  /* Per spec, GROUPS mode requires an ORDER BY clause */
2941  if (wc->frameOptions & FRAMEOPTION_GROUPS)
2942  {
2943  if (wc->orderClause == NIL)
2944  ereport(ERROR,
2945  (errcode(ERRCODE_WINDOWING_ERROR),
2946  errmsg("GROUPS mode requires an ORDER BY clause"),
2947  parser_errposition(pstate, windef->location)));
2948  }
2949 
2950  /* Process frame offset expressions */
2951  wc->startOffset = transformFrameOffset(pstate, wc->frameOptions,
2952  rangeopfamily, rangeopcintype,
2953  &wc->startInRangeFunc,
2954  windef->startOffset);
2955  wc->endOffset = transformFrameOffset(pstate, wc->frameOptions,
2956  rangeopfamily, rangeopcintype,
2957  &wc->endInRangeFunc,
2958  windef->endOffset);
2959  wc->winref = winref;
2960 
2961  result = lappend(result, wc);
2962  }
2963 
2964  return result;
2965 }
2966 
2967 /*
2968  * transformDistinctClause -
2969  * transform a DISTINCT clause
2970  *
2971  * Since we may need to add items to the query's targetlist, that list
2972  * is passed by reference.
2973  *
2974  * As with GROUP BY, we absorb the sorting semantics of ORDER BY as much as
2975  * possible into the distinctClause. This avoids a possible need to re-sort,
2976  * and allows the user to choose the equality semantics used by DISTINCT,
2977  * should she be working with a datatype that has more than one equality
2978  * operator.
2979  *
2980  * is_agg is true if we are transforming an aggregate(DISTINCT ...)
2981  * function call. This does not affect any behavior, only the phrasing
2982  * of error messages.
2983  */
2984 List *
2986  List **targetlist, List *sortClause, bool is_agg)
2987 {
2988  List *result = NIL;
2989  ListCell *slitem;
2990  ListCell *tlitem;
2991 
2992  /*
2993  * The distinctClause should consist of all ORDER BY items followed by all
2994  * other non-resjunk targetlist items. There must not be any resjunk
2995  * ORDER BY items --- that would imply that we are sorting by a value that
2996  * isn't necessarily unique within a DISTINCT group, so the results
2997  * wouldn't be well-defined. This construction ensures we follow the rule
2998  * that sortClause and distinctClause match; in fact the sortClause will
2999  * always be a prefix of distinctClause.
3000  *
3001  * Note a corner case: the same TLE could be in the ORDER BY list multiple
3002  * times with different sortops. We have to include it in the
3003  * distinctClause the same way to preserve the prefix property. The net
3004  * effect will be that the TLE value will be made unique according to both
3005  * sortops.
3006  */
3007  foreach(slitem, sortClause)
3008  {
3009  SortGroupClause *scl = (SortGroupClause *) lfirst(slitem);
3010  TargetEntry *tle = get_sortgroupclause_tle(scl, *targetlist);
3011 
3012  if (tle->resjunk)
3013  ereport(ERROR,
3014  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
3015  is_agg ?
3016  errmsg("in an aggregate with DISTINCT, ORDER BY expressions must appear in argument list") :
3017  errmsg("for SELECT DISTINCT, ORDER BY expressions must appear in select list"),
3018  parser_errposition(pstate,
3019  exprLocation((Node *) tle->expr))));
3020  result = lappend(result, copyObject(scl));
3021  }
3022 
3023  /*
3024  * Now add any remaining non-resjunk tlist items, using default sort/group
3025  * semantics for their data types.
3026  */
3027  foreach(tlitem, *targetlist)
3028  {
3029  TargetEntry *tle = (TargetEntry *) lfirst(tlitem);
3030 
3031  if (tle->resjunk)
3032  continue; /* ignore junk */
3033  result = addTargetToGroupList(pstate, tle,
3034  result, *targetlist,
3035  exprLocation((Node *) tle->expr));
3036  }
3037 
3038  /*
3039  * Complain if we found nothing to make DISTINCT. Returning an empty list
3040  * would cause the parsed Query to look like it didn't have DISTINCT, with
3041  * results that would probably surprise the user. Note: this case is
3042  * presently impossible for aggregates because of grammar restrictions,
3043  * but we check anyway.
3044  */
3045  if (result == NIL)
3046  ereport(ERROR,
3047  (errcode(ERRCODE_SYNTAX_ERROR),
3048  is_agg ?
3049  errmsg("an aggregate with DISTINCT must have at least one argument") :
3050  errmsg("SELECT DISTINCT must have at least one column")));
3051 
3052  return result;
3053 }
3054 
3055 /*
3056  * transformDistinctOnClause -
3057  * transform a DISTINCT ON clause
3058  *
3059  * Since we may need to add items to the query's targetlist, that list
3060  * is passed by reference.
3061  *
3062  * As with GROUP BY, we absorb the sorting semantics of ORDER BY as much as
3063  * possible into the distinctClause. This avoids a possible need to re-sort,
3064  * and allows the user to choose the equality semantics used by DISTINCT,
3065  * should she be working with a datatype that has more than one equality
3066  * operator.
3067  */
3068 List *
3070  List **targetlist, List *sortClause)
3071 {
3072  List *result = NIL;
3073  List *sortgrouprefs = NIL;
3074  bool skipped_sortitem;
3075  ListCell *lc;
3076  ListCell *lc2;
3077 
3078  /*
3079  * Add all the DISTINCT ON expressions to the tlist (if not already
3080  * present, they are added as resjunk items). Assign sortgroupref numbers
3081  * to them, and make a list of these numbers. (NB: we rely below on the
3082  * sortgrouprefs list being one-for-one with the original distinctlist.
3083  * Also notice that we could have duplicate DISTINCT ON expressions and
3084  * hence duplicate entries in sortgrouprefs.)
3085  */
3086  foreach(lc, distinctlist)
3087  {
3088  Node *dexpr = (Node *) lfirst(lc);
3089  int sortgroupref;
3090  TargetEntry *tle;
3091 
3092  tle = findTargetlistEntrySQL92(pstate, dexpr, targetlist,
3094  sortgroupref = assignSortGroupRef(tle, *targetlist);
3095  sortgrouprefs = lappend_int(sortgrouprefs, sortgroupref);
3096  }
3097 
3098  /*
3099  * If the user writes both DISTINCT ON and ORDER BY, adopt the sorting
3100  * semantics from ORDER BY items that match DISTINCT ON items, and also
3101  * adopt their column sort order. We insist that the distinctClause and
3102  * sortClause match, so throw error if we find the need to add any more
3103  * distinctClause items after we've skipped an ORDER BY item that wasn't
3104  * in DISTINCT ON.
3105  */
3106  skipped_sortitem = false;
3107  foreach(lc, sortClause)
3108  {
3109  SortGroupClause *scl = (SortGroupClause *) lfirst(lc);
3110 
3111  if (list_member_int(sortgrouprefs, scl->tleSortGroupRef))
3112  {
3113  if (skipped_sortitem)
3114  ereport(ERROR,
3115  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
3116  errmsg("SELECT DISTINCT ON expressions must match initial ORDER BY expressions"),
3117  parser_errposition(pstate,
3119  sortgrouprefs,
3120  distinctlist))));
3121  else
3122  result = lappend(result, copyObject(scl));
3123  }
3124  else
3125  skipped_sortitem = true;
3126  }
3127 
3128  /*
3129  * Now add any remaining DISTINCT ON items, using default sort/group
3130  * semantics for their data types. (Note: this is pretty questionable; if
3131  * the ORDER BY list doesn't include all the DISTINCT ON items and more
3132  * besides, you certainly aren't using DISTINCT ON in the intended way,
3133  * and you probably aren't going to get consistent results. It might be
3134  * better to throw an error or warning here. But historically we've
3135  * allowed it, so keep doing so.)
3136  */
3137  forboth(lc, distinctlist, lc2, sortgrouprefs)
3138  {
3139  Node *dexpr = (Node *) lfirst(lc);
3140  int sortgroupref = lfirst_int(lc2);
3141  TargetEntry *tle = get_sortgroupref_tle(sortgroupref, *targetlist);
3142 
3143  if (targetIsInSortList(tle, InvalidOid, result))
3144  continue; /* already in list (with some semantics) */
3145  if (skipped_sortitem)
3146  ereport(ERROR,
3147  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
3148  errmsg("SELECT DISTINCT ON expressions must match initial ORDER BY expressions"),
3149  parser_errposition(pstate, exprLocation(dexpr))));
3150  result = addTargetToGroupList(pstate, tle,
3151  result, *targetlist,
3152  exprLocation(dexpr));
3153  }
3154 
3155  /*
3156  * An empty result list is impossible here because of grammar
3157  * restrictions.
3158  */
3159  Assert(result != NIL);
3160 
3161  return result;
3162 }
3163 
3164 /*
3165  * get_matching_location
3166  * Get the exprLocation of the exprs member corresponding to the
3167  * (first) member of sortgrouprefs that equals sortgroupref.
3168  *
3169  * This is used so that we can point at a troublesome DISTINCT ON entry.
3170  * (Note that we need to use the original untransformed DISTINCT ON list
3171  * item, as whatever TLE it corresponds to will very possibly have a
3172  * parse location pointing to some matching entry in the SELECT list
3173  * or ORDER BY list.)
3174  */
3175 static int
3176 get_matching_location(int sortgroupref, List *sortgrouprefs, List *exprs)
3177 {
3178  ListCell *lcs;
3179  ListCell *lce;
3180 
3181  forboth(lcs, sortgrouprefs, lce, exprs)
3182  {
3183  if (lfirst_int(lcs) == sortgroupref)
3184  return exprLocation((Node *) lfirst(lce));
3185  }
3186  /* if no match, caller blew it */
3187  elog(ERROR, "get_matching_location: no matching sortgroupref");
3188  return -1; /* keep compiler quiet */
3189 }
3190 
3191 /*
3192  * resolve_unique_index_expr
3193  * Infer a unique index from a list of indexElems, for ON
3194  * CONFLICT clause
3195  *
3196  * Perform parse analysis of expressions and columns appearing within ON
3197  * CONFLICT clause. During planning, the returned list of expressions is used
3198  * to infer which unique index to use.
3199  */
3200 static List *
3202  Relation heapRel)
3203 {
3204  List *result = NIL;
3205  ListCell *l;
3206 
3207  foreach(l, infer->indexElems)
3208  {
3209  IndexElem *ielem = (IndexElem *) lfirst(l);
3211  Node *parse;
3212 
3213  /*
3214  * Raw grammar re-uses CREATE INDEX infrastructure for unique index
3215  * inference clause, and so will accept opclasses by name and so on.
3216  *
3217  * Make no attempt to match ASC or DESC ordering or NULLS FIRST/NULLS
3218  * LAST ordering, since those are not significant for inference
3219  * purposes (any unique index matching the inference specification in
3220  * other regards is accepted indifferently). Actively reject this as
3221  * wrong-headed.
3222  */
3223  if (ielem->ordering != SORTBY_DEFAULT)
3224  ereport(ERROR,
3225  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
3226  errmsg("ASC/DESC is not allowed in ON CONFLICT clause"),
3227  parser_errposition(pstate,
3228  exprLocation((Node *) infer))));
3229  if (ielem->nulls_ordering != SORTBY_NULLS_DEFAULT)
3230  ereport(ERROR,
3231  (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
3232  errmsg("NULLS FIRST/LAST is not allowed in ON CONFLICT clause"),
3233  parser_errposition(pstate,
3234  exprLocation((Node *) infer))));
3235 
3236  if (!ielem->expr)
3237  {
3238  /* Simple index attribute */
3239  ColumnRef *n;
3240 
3241  /*
3242  * Grammar won't have built raw expression for us in event of
3243  * plain column reference. Create one directly, and perform
3244  * expression transformation. Planner expects this, and performs
3245  * its own normalization for the purposes of matching against
3246  * pg_index.
3247  */
3248  n = makeNode(ColumnRef);
3249  n->fields = list_make1(makeString(ielem->name));
3250  /* Location is approximately that of inference specification */
3251  n->location = infer->location;
3252  parse = (Node *) n;
3253  }
3254  else
3255  {
3256  /* Do parse transformation of the raw expression */
3257  parse = (Node *) ielem->expr;
3258  }
3259 
3260  /*
3261  * transformExpr() will reject subqueries, aggregates, window
3262  * functions, and SRFs, based on being passed
3263  * EXPR_KIND_INDEX_EXPRESSION. So we needn't worry about those
3264  * further ... not that they would match any available index
3265  * expression anyway.
3266  */
3267  pInfer->expr = transformExpr(pstate, parse, EXPR_KIND_INDEX_EXPRESSION);
3268 
3269  /* Perform lookup of collation and operator class as required */
3270  if (!ielem->collation)
3271  pInfer->infercollid = InvalidOid;
3272  else
3273  pInfer->infercollid = LookupCollation(pstate, ielem->collation,
3274  exprLocation(pInfer->expr));
3275 
3276  if (!ielem->opclass)
3277  pInfer->inferopclass = InvalidOid;
3278  else
3279  pInfer->inferopclass = get_opclass_oid(BTREE_AM_OID,
3280  ielem->opclass, false);
3281 
3282  result = lappend(result, pInfer);
3283  }
3284 
3285  return result;
3286 }
3287 
3288 /*
3289  * transformOnConflictArbiter -
3290  * transform arbiter expressions in an ON CONFLICT clause.
3291  *
3292  * Transformed expressions used to infer one unique index relation to serve as
3293  * an ON CONFLICT arbiter. Partial unique indexes may be inferred using WHERE
3294  * clause from inference specification clause.
3295  */
3296 void
3298  OnConflictClause *onConflictClause,
3299  List **arbiterExpr, Node **arbiterWhere,
3300  Oid *constraint)
3301 {
3302  InferClause *infer = onConflictClause->infer;
3303 
3304  *arbiterExpr = NIL;
3305  *arbiterWhere = NULL;
3306  *constraint = InvalidOid;
3307 
3308  if (onConflictClause->action == ONCONFLICT_UPDATE && !infer)
3309  ereport(ERROR,
3310  (errcode(ERRCODE_SYNTAX_ERROR),
3311  errmsg("ON CONFLICT DO UPDATE requires inference specification or constraint name"),
3312  errhint("For example, ON CONFLICT (column_name)."),
3313  parser_errposition(pstate,
3314  exprLocation((Node *) onConflictClause))));
3315 
3316  /*
3317  * To simplify certain aspects of its design, speculative insertion into
3318  * system catalogs is disallowed
3319  */
3320  if (IsCatalogRelation(pstate->p_target_relation))
3321  ereport(ERROR,
3322  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3323  errmsg("ON CONFLICT is not supported with system catalog tables"),
3324  parser_errposition(pstate,
3325  exprLocation((Node *) onConflictClause))));
3326 
3327  /* Same applies to table used by logical decoding as catalog table */
3329  ereport(ERROR,
3330  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3331  errmsg("ON CONFLICT is not supported on table \"%s\" used as a catalog table",
3333  parser_errposition(pstate,
3334  exprLocation((Node *) onConflictClause))));
3335 
3336  /* ON CONFLICT DO NOTHING does not require an inference clause */
3337  if (infer)
3338  {
3339  if (infer->indexElems)
3340  *arbiterExpr = resolve_unique_index_expr(pstate, infer,
3341  pstate->p_target_relation);
3342 
3343  /*
3344  * Handling inference WHERE clause (for partial unique index
3345  * inference)
3346  */
3347  if (infer->whereClause)
3348  *arbiterWhere = transformExpr(pstate, infer->whereClause,
3350 
3351  /*
3352  * If the arbiter is specified by constraint name, get the constraint
3353  * OID and mark the constrained columns as requiring SELECT privilege,
3354  * in the same way as would have happened if the arbiter had been
3355  * specified by explicit reference to the constraint's index columns.
3356  */
3357  if (infer->conname)
3358  {
3359  Oid relid = RelationGetRelid(pstate->p_target_relation);
3360  RTEPermissionInfo *perminfo = pstate->p_target_nsitem->p_perminfo;
3361  Bitmapset *conattnos;
3362 
3363  conattnos = get_relation_constraint_attnos(relid, infer->conname,
3364  false, constraint);
3365 
3366  /* Make sure the rel as a whole is marked for SELECT access */
3367  perminfo->requiredPerms |= ACL_SELECT;
3368  /* Mark the constrained columns as requiring SELECT access */
3369  perminfo->selectedCols = bms_add_members(perminfo->selectedCols,
3370  conattnos);
3371  }
3372  }
3373 
3374  /*
3375  * It's convenient to form a list of expressions based on the
3376  * representation used by CREATE INDEX, since the same restrictions are
3377  * appropriate (e.g. on subqueries). However, from here on, a dedicated
3378  * primnode representation is used for inference elements, and so
3379  * assign_query_collations() can be trusted to do the right thing with the
3380  * post parse analysis query tree inference clause representation.
3381  */
3382 }
3383 
3384 /*
3385  * addTargetToSortList
3386  * If the given targetlist entry isn't already in the SortGroupClause
3387  * list, add it to the end of the list, using the given sort ordering
3388  * info.
3389  *
3390  * Returns the updated SortGroupClause list.
3391  */
3392 List *
3394  List *sortlist, List *targetlist, SortBy *sortby)
3395 {
3396  Oid restype = exprType((Node *) tle->expr);
3397  Oid sortop;
3398  Oid eqop;
3399  bool hashable;
3400  bool reverse;
3401  int location;
3402  ParseCallbackState pcbstate;
3403 
3404  /* if tlist item is an UNKNOWN literal, change it to TEXT */
3405  if (restype == UNKNOWNOID)
3406  {
3407  tle->expr = (Expr *) coerce_type(pstate, (Node *) tle->expr,
3408  restype, TEXTOID, -1,
3411  -1);
3412  restype = TEXTOID;
3413  }
3414 
3415  /*
3416  * Rather than clutter the API of get_sort_group_operators and the other
3417  * functions we're about to use, make use of error context callback to
3418  * mark any error reports with a parse position. We point to the operator
3419  * location if present, else to the expression being sorted. (NB: use the
3420  * original untransformed expression here; the TLE entry might well point
3421  * at a duplicate expression in the regular SELECT list.)
3422  */
3423  location = sortby->location;
3424  if (location < 0)
3425  location = exprLocation(sortby->node);
3426  setup_parser_errposition_callback(&pcbstate, pstate, location);
3427 
3428  /* determine the sortop, eqop, and directionality */
3429  switch (sortby->sortby_dir)
3430  {
3431  case SORTBY_DEFAULT:
3432  case SORTBY_ASC:
3433  get_sort_group_operators(restype,
3434  true, true, false,
3435  &sortop, &eqop, NULL,
3436  &hashable);
3437  reverse = false;
3438  break;
3439  case SORTBY_DESC:
3440  get_sort_group_operators(restype,
3441  false, true, true,
3442  NULL, &eqop, &sortop,
3443  &hashable);
3444  reverse = true;
3445  break;
3446  case SORTBY_USING:
3447  Assert(sortby->useOp != NIL);
3448  sortop = compatible_oper_opid(sortby->useOp,
3449  restype,
3450  restype,
3451  false);
3452 
3453  /*
3454  * Verify it's a valid ordering operator, fetch the corresponding
3455  * equality operator, and determine whether to consider it like
3456  * ASC or DESC.
3457  */
3458  eqop = get_equality_op_for_ordering_op(sortop, &reverse);
3459  if (!OidIsValid(eqop))
3460  ereport(ERROR,
3461  (errcode(ERRCODE_WRONG_OBJECT_TYPE),
3462  errmsg("operator %s is not a valid ordering operator",
3463  strVal(llast(sortby->useOp))),
3464  errhint("Ordering operators must be \"<\" or \">\" members of btree operator families.")));
3465 
3466  /*
3467  * Also see if the equality operator is hashable.
3468  */
3469  hashable = op_hashjoinable(eqop, restype);
3470  break;
3471  default:
3472  elog(ERROR, "unrecognized sortby_dir: %d", sortby->sortby_dir);
3473  sortop = InvalidOid; /* keep compiler quiet */
3474  eqop = InvalidOid;
3475  hashable = false;
3476  reverse = false;
3477  break;
3478  }
3479 
3481 
3482  /* avoid making duplicate sortlist entries */
3483  if (!targetIsInSortList(tle, sortop, sortlist))
3484  {
3486 
3487  sortcl->tleSortGroupRef = assignSortGroupRef(tle, targetlist);
3488 
3489  sortcl->eqop = eqop;
3490  sortcl->sortop = sortop;
3491  sortcl->hashable = hashable;
3492 
3493  switch (sortby->sortby_nulls)
3494  {
3495  case SORTBY_NULLS_DEFAULT:
3496  /* NULLS FIRST is default for DESC; other way for ASC */
3497  sortcl->nulls_first = reverse;
3498  break;
3499  case SORTBY_NULLS_FIRST:
3500  sortcl->nulls_first = true;
3501  break;
3502  case SORTBY_NULLS_LAST:
3503  sortcl->nulls_first = false;
3504  break;
3505  default:
3506  elog(ERROR, "unrecognized sortby_nulls: %d",
3507  sortby->sortby_nulls);
3508  break;
3509  }
3510 
3511  sortlist = lappend(sortlist, sortcl);
3512  }
3513 
3514  return sortlist;
3515 }
3516 
3517 /*
3518  * addTargetToGroupList
3519  * If the given targetlist entry isn't already in the SortGroupClause
3520  * list, add it to the end of the list, using default sort/group
3521  * semantics.
3522  *
3523  * This is very similar to addTargetToSortList, except that we allow the
3524  * case where only a grouping (equality) operator can be found, and that
3525  * the TLE is considered "already in the list" if it appears there with any
3526  * sorting semantics.
3527  *
3528  * location is the parse location to be fingered in event of trouble. Note
3529  * that we can't rely on exprLocation(tle->expr), because that might point
3530  * to a SELECT item that matches the GROUP BY item; it'd be pretty confusing
3531  * to report such a location.
3532  *
3533  * Returns the updated SortGroupClause list.
3534  */
3535 static List *
3537  List *grouplist, List *targetlist, int location)
3538 {
3539  Oid restype = exprType((Node *) tle->expr);
3540 
3541  /* if tlist item is an UNKNOWN literal, change it to TEXT */
3542  if (restype == UNKNOWNOID)
3543  {
3544  tle->expr = (Expr *) coerce_type(pstate, (Node *) tle->expr,
3545  restype, TEXTOID, -1,
3548  -1);
3549  restype = TEXTOID;
3550  }
3551 
3552  /* avoid making duplicate grouplist entries */
3553  if (!targetIsInSortList(tle, InvalidOid, grouplist))
3554  {
3556  Oid sortop;
3557  Oid eqop;
3558  bool hashable;
3559  ParseCallbackState pcbstate;
3560 
3561  setup_parser_errposition_callback(&pcbstate, pstate, location);
3562 
3563  /* determine the eqop and optional sortop */
3564  get_sort_group_operators(restype,
3565  false, true, false,
3566  &sortop, &eqop, NULL,
3567  &hashable);
3568 
3570 
3571  grpcl->tleSortGroupRef = assignSortGroupRef(tle, targetlist);
3572  grpcl->eqop = eqop;
3573  grpcl->sortop = sortop;
3574  grpcl->nulls_first = false; /* OK with or without sortop */
3575  grpcl->hashable = hashable;
3576 
3577  grouplist = lappend(grouplist, grpcl);
3578  }
3579 
3580  return grouplist;
3581 }
3582 
3583 /*
3584  * assignSortGroupRef
3585  * Assign the targetentry an unused ressortgroupref, if it doesn't
3586  * already have one. Return the assigned or pre-existing refnumber.
3587  *
3588  * 'tlist' is the targetlist containing (or to contain) the given targetentry.
3589  */
3590 Index
3592 {
3593  Index maxRef;
3594  ListCell *l;
3595 
3596  if (tle->ressortgroupref) /* already has one? */
3597  return tle->ressortgroupref;
3598 
3599  /* easiest way to pick an unused refnumber: max used + 1 */
3600  maxRef = 0;
3601  foreach(l, tlist)
3602  {
3603  Index ref = ((TargetEntry *) lfirst(l))->ressortgroupref;
3604 
3605  if (ref > maxRef)
3606  maxRef = ref;
3607  }
3608  tle->ressortgroupref = maxRef + 1;
3609  return tle->ressortgroupref;
3610 }
3611 
3612 /*
3613  * targetIsInSortList
3614  * Is the given target item already in the sortlist?
3615  * If sortop is not InvalidOid, also test for a match to the sortop.
3616  *
3617  * It is not an oversight that this function ignores the nulls_first flag.
3618  * We check sortop when determining if an ORDER BY item is redundant with
3619  * earlier ORDER BY items, because it's conceivable that "ORDER BY
3620  * foo USING <, foo USING <<<" is not redundant, if <<< distinguishes
3621  * values that < considers equal. We need not check nulls_first
3622  * however, because a lower-order column with the same sortop but
3623  * opposite nulls direction is redundant. Also, we can consider
3624  * ORDER BY foo ASC, foo DESC redundant, so check for a commutator match.
3625  *
3626  * Works for both ordering and grouping lists (sortop would normally be
3627  * InvalidOid when considering grouping). Note that the main reason we need
3628  * this routine (and not just a quick test for nonzeroness of ressortgroupref)
3629  * is that a TLE might be in only one of the lists.
3630  */
3631 bool
3632 targetIsInSortList(TargetEntry *tle, Oid sortop, List *sortList)
3633 {
3634  Index ref = tle->ressortgroupref;
3635  ListCell *l;
3636 
3637  /* no need to scan list if tle has no marker */
3638  if (ref == 0)
3639  return false;
3640 
3641  foreach(l, sortList)
3642  {
3643  SortGroupClause *scl = (SortGroupClause *) lfirst(l);
3644 
3645  if (scl->tleSortGroupRef == ref &&
3646  (sortop == InvalidOid ||
3647  sortop == scl->sortop ||
3648  sortop == get_commutator(scl->sortop)))
3649  return true;
3650  }
3651  return false;
3652 }
3653 
3654 /*
3655  * findWindowClause
3656  * Find the named WindowClause in the list, or return NULL if not there
3657  */
3658 static WindowClause *
3659 findWindowClause(List *wclist, const char *name)
3660 {
3661  ListCell *l;
3662 
3663  foreach(l, wclist)
3664  {
3665  WindowClause *wc = (WindowClause *) lfirst(l);
3666 
3667  if (wc->name && strcmp(wc->name, name) == 0)
3668  return wc;
3669  }
3670 
3671  return NULL;
3672 }
3673 
3674 /*
3675  * transformFrameOffset
3676  * Process a window frame offset expression
3677  *
3678  * In RANGE mode, rangeopfamily is the sort opfamily for the input ORDER BY
3679  * column, and rangeopcintype is the input data type the sort operator is
3680  * registered with. We expect the in_range function to be registered with
3681  * that same type. (In binary-compatible cases, it might be different from
3682  * the input column's actual type, so we can't use that for the lookups.)
3683  * We'll return the OID of the in_range function to *inRangeFunc.
3684  */
3685 static Node *
3686 transformFrameOffset(ParseState *pstate, int frameOptions,
3687  Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc,
3688  Node *clause)
3689 {
3690  const char *constructName = NULL;
3691  Node *node;
3692 
3693  *inRangeFunc = InvalidOid; /* default result */
3694 
3695  /* Quick exit if no offset expression */
3696  if (clause == NULL)
3697  return NULL;
3698 
3699  if (frameOptions & FRAMEOPTION_ROWS)
3700  {
3701  /* Transform the raw expression tree */
3702  node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_ROWS);
3703 
3704  /*
3705  * Like LIMIT clause, simply coerce to int8
3706  */
3707  constructName = "ROWS";
3708  node = coerce_to_specific_type(pstate, node, INT8OID, constructName);
3709  }
3710  else if (frameOptions & FRAMEOPTION_RANGE)
3711  {
3712  /*
3713  * We must look up the in_range support function that's to be used,
3714  * possibly choosing one of several, and coerce the "offset" value to
3715  * the appropriate input type.
3716  */
3717  Oid nodeType;
3718  Oid preferredType;
3719  int nfuncs = 0;
3720  int nmatches = 0;
3721  Oid selectedType = InvalidOid;
3722  Oid selectedFunc = InvalidOid;
3723  CatCList *proclist;
3724  int i;
3725 
3726  /* Transform the raw expression tree */
3727  node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_RANGE);
3728  nodeType = exprType(node);
3729 
3730  /*
3731  * If there are multiple candidates, we'll prefer the one that exactly
3732  * matches nodeType; or if nodeType is as yet unknown, prefer the one
3733  * that exactly matches the sort column type. (The second rule is
3734  * like what we do for "known_type operator unknown".)
3735  */
3736  preferredType = (nodeType != UNKNOWNOID) ? nodeType : rangeopcintype;
3737 
3738  /* Find the in_range support functions applicable to this case */
3739  proclist = SearchSysCacheList2(AMPROCNUM,
3740  ObjectIdGetDatum(rangeopfamily),
3741  ObjectIdGetDatum(rangeopcintype));
3742  for (i = 0; i < proclist->n_members; i++)
3743  {
3744  HeapTuple proctup = &proclist->members[i]->tuple;
3745  Form_pg_amproc procform = (Form_pg_amproc) GETSTRUCT(proctup);
3746 
3747  /* The search will find all support proc types; ignore others */
3748  if (procform->amprocnum != BTINRANGE_PROC)
3749  continue;
3750  nfuncs++;
3751 
3752  /* Ignore function if given value can't be coerced to that type */
3753  if (!can_coerce_type(1, &nodeType, &procform->amprocrighttype,
3755  continue;
3756  nmatches++;
3757 
3758  /* Remember preferred match, or any match if didn't find that */
3759  if (selectedType != preferredType)
3760  {
3761  selectedType = procform->amprocrighttype;
3762  selectedFunc = procform->amproc;
3763  }
3764  }
3765  ReleaseCatCacheList(proclist);
3766 
3767  /*
3768  * Throw error if needed. It seems worth taking the trouble to
3769  * distinguish "no support at all" from "you didn't match any
3770  * available offset type".
3771  */
3772  if (nfuncs == 0)
3773  ereport(ERROR,
3774  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3775  errmsg("RANGE with offset PRECEDING/FOLLOWING is not supported for column type %s",
3776  format_type_be(rangeopcintype)),
3777  parser_errposition(pstate, exprLocation(node))));
3778  if (nmatches == 0)
3779  ereport(ERROR,
3780  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3781  errmsg("RANGE with offset PRECEDING/FOLLOWING is not supported for column type %s and offset type %s",
3782  format_type_be(rangeopcintype),
3783  format_type_be(nodeType)),
3784  errhint("Cast the offset value to an appropriate type."),
3785  parser_errposition(pstate, exprLocation(node))));
3786  if (nmatches != 1 && selectedType != preferredType)
3787  ereport(ERROR,
3788  (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
3789  errmsg("RANGE with offset PRECEDING/FOLLOWING has multiple interpretations for column type %s and offset type %s",
3790  format_type_be(rangeopcintype),
3791  format_type_be(nodeType)),
3792  errhint("Cast the offset value to the exact intended type."),
3793  parser_errposition(pstate, exprLocation(node))));
3794 
3795  /* OK, coerce the offset to the right type */
3796  constructName = "RANGE";
3797  node = coerce_to_specific_type(pstate, node,
3798  selectedType, constructName);
3799  *inRangeFunc = selectedFunc;
3800  }
3801  else if (frameOptions & FRAMEOPTION_GROUPS)
3802  {
3803  /* Transform the raw expression tree */
3804  node = transformExpr(pstate, clause, EXPR_KIND_WINDOW_FRAME_GROUPS);
3805 
3806  /*
3807  * Like LIMIT clause, simply coerce to int8
3808  */
3809  constructName = "GROUPS";
3810  node = coerce_to_specific_type(pstate, node, INT8OID, constructName);
3811  }
3812  else
3813  {
3814  Assert(false);
3815  node = NULL;
3816  }
3817 
3818  /* Disallow variables in frame offsets */
3819  checkExprIsVarFree(pstate, node, constructName);
3820 
3821  return node;
3822 }
bool bms_is_member(int x, const Bitmapset *a)
Definition: bitmapset.c:510
Bitmapset * bms_add_member(Bitmapset *a, int x)
Definition: bitmapset.c:815
Bitmapset * bms_add_members(Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:917
signed short int16
Definition: c.h:493
signed int int32
Definition: c.h:494
#define Assert(condition)
Definition: c.h:858
unsigned int Index
Definition: c.h:614
#define OidIsValid(objectId)
Definition: c.h:775
bool IsCatalogRelation(Relation relation)
Definition: catalog.c:103
void ReleaseCatCacheList(CatCList *list)
Definition: catcache.c:1986
int errmsg_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...)
Definition: elog.c:1180
int errhint(const char *fmt,...)
Definition: elog.c:1317
int errcode(int sqlerrcode)
Definition: elog.c:857
int errmsg(const char *fmt,...)
Definition: elog.c:1070
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
#define ereport(elevel,...)
Definition: elog.h:149
bool equal(const void *a, const void *b)
Definition: equalfuncs.c:223
char * format_type_be(Oid type_oid)
Definition: format_type.c:343
#define GETSTRUCT(TUP)
Definition: htup_details.h:653
int j
Definition: isn.c:74
int i
Definition: isn.c:73
List * list_truncate(List *list, int new_size)
Definition: list.c:631
List * lappend(List *list, void *datum)
Definition: list.c:339
List * lappend_int(List *list, int datum)
Definition: list.c:357
List * lappend_oid(List *list, Oid datum)
Definition: list.c:375
bool list_member_int(const List *list, int datum)
Definition: list.c:702
List * list_concat(List *list1, const List *list2)
Definition: list.c:561
#define NoLock
Definition: lockdefs.h:34
#define RowExclusiveLock
Definition: lockdefs.h:38
Oid get_equality_op_for_ordering_op(Oid opno, bool *reverse)
Definition: lsyscache.c:267
bool op_hashjoinable(Oid opno, Oid inputtype)
Definition: lsyscache.c:1437
Oid get_typcollation(Oid typid)
Definition: lsyscache.c:3056
bool get_ordering_op_properties(Oid opno, Oid *opfamily, Oid *opcintype, int16 *strategy)
Definition: lsyscache.c:207
Oid get_func_rettype(Oid funcid)
Definition: lsyscache.c:1655
Oid get_commutator(Oid opno)
Definition: lsyscache.c:1509
RelabelType * makeRelabelType(Expr *arg, Oid rtype, int32 rtypmod, Oid rcollid, CoercionForm rformat)
Definition: makefuncs.c:404
GroupingSet * makeGroupingSet(GroupingSetKind kind, List *content, int location)
Definition: makefuncs.c:817
Var * makeVar(int varno, AttrNumber varattno, Oid vartype, int32 vartypmod, Oid varcollid, Index varlevelsup)
Definition: makefuncs.c:66
Expr * makeBoolExpr(BoolExprType boolop, List *args, int location)
Definition: makefuncs.c:371
FuncCall * makeFuncCall(List *name, List *args, CoercionForm funcformat, int location)
Definition: makefuncs.c:603
A_Expr * makeSimpleA_Expr(A_Expr_Kind kind, char *name, Node *lexpr, Node *rexpr, int location)
Definition: makefuncs.c:48
char * pstrdup(const char *in)
Definition: mcxt.c:1695
void pfree(void *pointer)
Definition: mcxt.c:1520
void * palloc0(Size size)
Definition: mcxt.c:1346
void * palloc(Size size)
Definition: mcxt.c:1316
char * NameListToString(const List *names)
Definition: namespace.c:3579
#define BTINRANGE_PROC
Definition: nbtree.h:709
Oid exprType(const Node *expr)
Definition: nodeFuncs.c:42
int32 exprTypmod(const Node *expr)
Definition: nodeFuncs.c:298
Oid exprCollation(const Node *expr)
Definition: nodeFuncs.c:816
int exprLocation(const Node *expr)
Definition: nodeFuncs.c:1386
Node * strip_implicit_coercions(Node *node)
Definition: nodeFuncs.c:700
#define IsA(nodeptr, _type_)
Definition: nodes.h:158
#define copyObject(obj)
Definition: nodes.h:224
#define nodeTag(nodeptr)
Definition: nodes.h:133
@ ONCONFLICT_UPDATE
Definition: nodes.h:419
@ CMD_SELECT
Definition: nodes.h:265
LimitOption
Definition: nodes.h:429
@ LIMIT_OPTION_WITH_TIES
Definition: nodes.h:431
#define makeNode(_type_)
Definition: nodes.h:155
#define castNode(_type_, nodeptr)
Definition: nodes.h:176
JoinType
Definition: nodes.h:288
@ JOIN_FULL
Definition: nodes.h:295
@ JOIN_INNER
Definition: nodes.h:293
@ JOIN_RIGHT
Definition: nodes.h:296
@ JOIN_LEFT
Definition: nodes.h:294
Oid get_opclass_oid(Oid amID, List *opclassname, bool missing_ok)
Definition: opclasscmds.c:219
Index assignSortGroupRef(TargetEntry *tle, List *tlist)
static Node * transformJoinOnClause(ParseState *pstate, JoinExpr *j, List *namespace)
Definition: parse_clause.c:367
static int extractRemainingColumns(ParseState *pstate, ParseNamespaceColumn *src_nscolumns, List *src_colnames, List **src_colnos, List **res_colnames, List **res_colvars, ParseNamespaceColumn *res_nscolumns)
Definition: parse_clause.c:255
static void setNamespaceLateralState(List *namespace, bool lateral_only, bool lateral_ok)
List * transformWindowDefinitions(ParseState *pstate, List *windowdefs, List **targetlist)
List * addTargetToSortList(ParseState *pstate, TargetEntry *tle, List *sortlist, List *targetlist, SortBy *sortby)
static void markRelsAsNulledBy(ParseState *pstate, Node *n, int jindex)
static void checkExprIsVarFree(ParseState *pstate, Node *n, const char *constructName)
List * transformDistinctOnClause(ParseState *pstate, List *distinctlist, List **targetlist, List *sortClause)
static ParseNamespaceItem * transformRangeSubselect(ParseState *pstate, RangeSubselect *r)
Definition: parse_clause.c:407
Node * transformLimitClause(ParseState *pstate, Node *clause, ParseExprKind exprKind, const char *constructName, LimitOption limitOption)
static List * transformGroupClauseList(List **flatresult, ParseState *pstate, List *list, List **targetlist, List *sortClause, ParseExprKind exprKind, bool useSQL99, bool toplevel)
List * transformSortClause(ParseState *pstate, List *orderlist, List **targetlist, ParseExprKind exprKind, bool useSQL99)
static Node * transformGroupingSet(List **flatresult, ParseState *pstate, GroupingSet *gset, List **targetlist, List *sortClause, ParseExprKind exprKind, bool useSQL99, bool toplevel)
static Node * flatten_grouping_sets(Node *expr, bool toplevel, bool *hasGroupingSets)
Node * transformWhereClause(ParseState *pstate, Node *clause, ParseExprKind exprKind, const char *constructName)
static Var * buildVarFromNSColumn(ParseState *pstate, ParseNamespaceColumn *nscol)
static ParseNamespaceItem * transformRangeTableFunc(ParseState *pstate, RangeTableFunc *rtf)
Definition: parse_clause.c:688
static void setNamespaceColumnVisibility(List *namespace, bool cols_visible)
static int get_matching_location(int sortgroupref, List *sortgrouprefs, List *exprs)
void transformFromClause(ParseState *pstate, List *frmList)
Definition: parse_clause.c:114
static ParseNamespaceItem * getNSItemForSpecialRelationTypes(ParseState *pstate, RangeVar *rv)
static void checkTargetlistEntrySQL92(ParseState *pstate, TargetEntry *tle, ParseExprKind exprKind)
List * transformGroupClause(ParseState *pstate, List *grouplist, List **groupingSets, List **targetlist, List *sortClause, ParseExprKind exprKind, bool useSQL99)
static Index transformGroupClauseExpr(List **flatresult, Bitmapset *seen_local, ParseState *pstate, Node *gexpr, List **targetlist, List *sortClause, ParseExprKind exprKind, bool useSQL99, bool toplevel)
List * transformDistinctClause(ParseState *pstate, List **targetlist, List *sortClause, bool is_agg)
static TableSampleClause * transformRangeTableSample(ParseState *pstate, RangeTableSample *rts)
Definition: parse_clause.c:910
static TargetEntry * findTargetlistEntrySQL99(ParseState *pstate, Node *node, List **tlist, ParseExprKind exprKind)
bool targetIsInSortList(TargetEntry *tle, Oid sortop, List *sortList)
static List * addTargetToGroupList(ParseState *pstate, TargetEntry *tle, List *grouplist, List *targetlist, int location)
static Node * transformFrameOffset(ParseState *pstate, int frameOptions, Oid rangeopfamily, Oid rangeopcintype, Oid *inRangeFunc, Node *clause)
static List * resolve_unique_index_expr(ParseState *pstate, InferClause *infer, Relation heapRel)
void transformOnConflictArbiter(ParseState *pstate, OnConflictClause *onConflictClause, List **arbiterExpr, Node **arbiterWhere, Oid *constraint)
static Node * transformJoinUsingClause(ParseState *pstate, List *leftVars, List *rightVars)
Definition: parse_clause.c:308
int setTargetTable(ParseState *pstate, RangeVar *relation, bool inh, bool alsoSource, AclMode requiredPerms)
Definition: parse_clause.c:180
static Node * buildMergedJoinVar(ParseState *pstate, JoinType jointype, Var *l_colvar, Var *r_colvar)
static Node * transformFromClauseItem(ParseState *pstate, Node *n, ParseNamespaceItem **top_nsitem, List **namespace)
static ParseNamespaceItem * transformTableEntry(ParseState *pstate, RangeVar *r)
Definition: parse_clause.c:397
static TargetEntry * findTargetlistEntrySQL92(ParseState *pstate, Node *node, List **tlist, ParseExprKind exprKind)
static WindowClause * findWindowClause(List *wclist, const char *name)
static ParseNamespaceItem * transformRangeFunction(ParseState *pstate, RangeFunction *r)
Definition: parse_clause.c:465
Node * coerce_to_specific_type_typmod(ParseState *pstate, Node *node, Oid targetTypeId, int32 targetTypmod, const char *constructName)
Node * coerce_type(ParseState *pstate, Node *node, Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod, CoercionContext ccontext, CoercionForm cformat, int location)
Definition: parse_coerce.c:157
Node * coerce_to_boolean(ParseState *pstate, Node *node, const char *constructName)
int32 select_common_typmod(ParseState *pstate, List *exprs, Oid common_type)
Node * coerce_to_specific_type(ParseState *pstate, Node *node, Oid targetTypeId, const char *constructName)
Oid select_common_type(ParseState *pstate, List *exprs, const char *context, Node **which_expr)
bool can_coerce_type(int nargs, const Oid *input_typeids, const Oid *target_typeids, CoercionContext ccontext)
Definition: parse_coerce.c:556
void assign_list_collations(ParseState *pstate, List *exprs)
void assign_expr_collations(ParseState *pstate, Node *expr)
Node * transformExpr(ParseState *pstate, Node *expr, ParseExprKind exprKind)
Definition: parse_expr.c:121
const char * ParseExprKindName(ParseExprKind exprKind)
Definition: parse_expr.c:3111
Oid LookupFuncName(List *funcname, int nargs, const Oid *argtypes, bool missing_ok)
Definition: parse_func.c:2144
ParseNamespaceItem * transformJsonTable(ParseState *pstate, JsonTable *jt)
void cancel_parser_errposition_callback(ParseCallbackState *pcbstate)
Definition: parse_node.c:156
int parser_errposition(ParseState *pstate, int location)
Definition: parse_node.c:106
void setup_parser_errposition_callback(ParseCallbackState *pcbstate, ParseState *pstate, int location)
Definition: parse_node.c:140
ParseExprKind
Definition: parse_node.h:39
@ EXPR_KIND_DISTINCT_ON
Definition: parse_node.h:61
@ EXPR_KIND_INDEX_EXPRESSION
Definition: parse_node.h:72
@ EXPR_KIND_WINDOW_FRAME_RANGE
Definition: parse_node.h:51
@ EXPR_KIND_FROM_SUBSELECT
Definition: parse_node.h:44
@ EXPR_KIND_WINDOW_FRAME_GROUPS
Definition: parse_node.h:53
@ EXPR_KIND_JOIN_USING
Definition: parse_node.h:43
@ EXPR_KIND_INDEX_PREDICATE
Definition: parse_node.h:73
@ EXPR_KIND_ORDER_BY
Definition: parse_node.h:60
@ EXPR_KIND_JOIN_ON
Definition: parse_node.h:42
@ EXPR_KIND_LIMIT
Definition: parse_node.h:62
@ EXPR_KIND_NONE
Definition: parse_node.h:40
@ EXPR_KIND_GROUP_BY
Definition: parse_node.h:59
@ EXPR_KIND_FROM_FUNCTION
Definition: parse_node.h:45
@ EXPR_KIND_WINDOW_PARTITION
Definition: parse_node.h:49
@ EXPR_KIND_WINDOW_FRAME_ROWS
Definition: parse_node.h:52
@ EXPR_KIND_WINDOW_ORDER
Definition: parse_node.h:50
struct ParseNamespaceColumn ParseNamespaceColumn
Definition: parse_node.h:25
void get_sort_group_operators(Oid argtype, bool needLT, bool needEQ, bool needGT, Oid *ltOpr, Oid *eqOpr, Oid *gtOpr, bool *isHashable)
Definition: parse_oper.c:180
Oid compatible_oper_opid(List *op, Oid arg1, Oid arg2, bool noError)
Definition: parse_oper.c:487
void markNullableIfNeeded(ParseState *pstate, Var *var)
ParseNamespaceItem * addRangeTableEntryForCTE(ParseState *pstate, CommonTableExpr *cte, Index levelsup, RangeVar *rv, bool inFromCl)
ParseNamespaceItem * addRangeTableEntry(ParseState *pstate, RangeVar *relation, Alias *alias, bool inh, bool inFromCl)
ParseNamespaceItem * addRangeTableEntryForJoin(ParseState *pstate, List *colnames, ParseNamespaceColumn *nscolumns, JoinType jointype, int nummergedcols, List *aliasvars, List *leftcols, List *rightcols, Alias *join_using_alias, Alias *alias, bool inFromCl)
void markVarForSelectPriv(ParseState *pstate, Var *var)
CommonTableExpr * scanNameSpaceForCTE(ParseState *pstate, const char *refname, Index *ctelevelsup)
ParseNamespaceItem * addRangeTableEntryForRelation(ParseState *pstate, Relation rel, int lockmode, Alias *alias, bool inh, bool inFromCl)
Relation parserOpenTable(ParseState *pstate, const RangeVar *relation, int lockmode)
void addNSItemToQuery(ParseState *pstate, ParseNamespaceItem *nsitem, bool addToJoinList, bool addToRelNameSpace, bool addToVarNameSpace)
ParseNamespaceItem * addRangeTableEntryForSubquery(ParseState *pstate, Query *subquery, Alias *alias, bool lateral, bool inFromCl)
bool scanNameSpaceForENR(ParseState *pstate, const char *refname)
bool isLockedRefname(ParseState *pstate, const char *refname)
ParseNamespaceItem * addRangeTableEntryForFunction(ParseState *pstate, List *funcnames, List *funcexprs, List *coldeflists, RangeFunction *rangefunc, bool lateral, bool inFromCl)
Node * colNameToVar(ParseState *pstate, const char *colname, bool localonly, int location)
ParseNamespaceItem * addRangeTableEntryForTableFunc(ParseState *pstate, TableFunc *tf, Alias *alias, bool lateral, bool inFromCl)
ParseNamespaceItem * addRangeTableEntryForENR(ParseState *pstate, RangeVar *rv, bool inFromCl)
void checkNameSpaceConflicts(ParseState *pstate, List *namespace1, List *namespace2)
TargetEntry * transformTargetEntry(ParseState *pstate, Node *node, Node *expr, ParseExprKind exprKind, char *colname, bool resjunk)
Definition: parse_target.c:75
char * FigureColname(Node *node)
Oid LookupCollation(ParseState *pstate, List *collnames, int location)
Definition: parse_type.c:515
void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName, Oid *typeid_p, int32 *typmod_p)
Definition: parse_type.c:310
#define FRAMEOPTION_END_OFFSET
Definition: parsenodes.h:602
@ SORTBY_NULLS_DEFAULT
Definition: parsenodes.h:54
@ SORTBY_NULLS_LAST
Definition: parsenodes.h:56
@ SORTBY_NULLS_FIRST
Definition: parsenodes.h:55
@ GROUPING_SET_CUBE
Definition: parsenodes.h:1505
@ GROUPING_SET_SIMPLE
Definition: parsenodes.h:1503
@ GROUPING_SET_ROLLUP
Definition: parsenodes.h:1504
@ GROUPING_SET_SETS
Definition: parsenodes.h:1506
@ GROUPING_SET_EMPTY
Definition: parsenodes.h:1502
uint64 AclMode
Definition: parsenodes.h:74
@ AEXPR_OP
Definition: parsenodes.h:313
@ RTE_RELATION
Definition: parsenodes.h:1028
#define FRAMEOPTION_START_OFFSET
Definition: parsenodes.h:600
#define FRAMEOPTION_RANGE
Definition: parsenodes.h:582
#define ACL_SELECT
Definition: parsenodes.h:77
#define FRAMEOPTION_GROUPS
Definition: parsenodes.h:584
#define FRAMEOPTION_DEFAULTS
Definition: parsenodes.h:608
@ SORTBY_USING
Definition: parsenodes.h:49
@ SORTBY_DESC
Definition: parsenodes.h:48
@ SORTBY_ASC
Definition: parsenodes.h:47
@ SORTBY_DEFAULT
Definition: parsenodes.h:46
#define FRAMEOPTION_ROWS
Definition: parsenodes.h:583
Query * parse_sub_analyze(Node *parseTree, ParseState *parentParseState, CommonTableExpr *parentCTE, bool locked_from_parent, bool resolve_unknowns)
Definition: analyze.c:221
List * SystemFuncName(char *name)
FormData_pg_amproc * Form_pg_amproc
Definition: pg_amproc.h:68
int16 attnum
Definition: pg_attribute.h:74
void * arg
Bitmapset * get_relation_constraint_attnos(Oid relid, const char *conname, bool missing_ok, Oid *constraintOid)
#define lfirst(lc)
Definition: pg_list.h:172
#define llast(l)
Definition: pg_list.h:198
#define lfirst_node(type, lc)
Definition: pg_list.h:176
static int list_length(const List *l)
Definition: pg_list.h:152
#define linitial_node(type, l)
Definition: pg_list.h:181
#define NIL
Definition: pg_list.h:68
#define forboth(cell1, list1, cell2, list2)
Definition: pg_list.h:518
#define lfirst_int(lc)
Definition: pg_list.h:173
#define list_make1(x1)
Definition: pg_list.h:212
static ListCell * list_nth_cell(const List *list, int n)
Definition: pg_list.h:277
#define linitial(l)
Definition: pg_list.h:178
#define lsecond(l)
Definition: pg_list.h:183
#define list_make1_int(x1)
Definition: pg_list.h:227
#define lfirst_oid(lc)
Definition: pg_list.h:174
#define list_make2(x1, x2)
Definition: pg_list.h:214
void check_stack_depth(void)
Definition: postgres.c:3531
static Datum ObjectIdGetDatum(Oid X)
Definition: postgres.h:252
#define InvalidOid
Definition: postgres_ext.h:36
unsigned int Oid
Definition: postgres_ext.h:31
char * c
e
Definition: preproc-init.c:82
static int fc(const char *x)
Definition: preproc-init.c:99
@ TFT_XMLTABLE
Definition: primnodes.h:99
@ AND_EXPR
Definition: primnodes.h:931
@ COERCE_IMPLICIT_CAST
Definition: primnodes.h:736
@ COERCE_EXPLICIT_CALL
Definition: primnodes.h:734
@ COERCION_IMPLICIT
Definition: primnodes.h:714
static struct subre * parse(struct vars *v, int stopper, int type, struct state *init, struct state *final)
Definition: regcomp.c:715
#define RelationGetRelid(relation)
Definition: rel.h:505
#define RelationIsUsedAsCatalogTable(relation)
Definition: rel.h:386
#define RelationGetRelationName(relation)
Definition: rel.h:539
bool contain_windowfuncs(Node *node)
Definition: rewriteManip.c:215
int locate_agg_of_level(Node *node, int levelsup)
Definition: rewriteManip.c:149
bool contain_aggs_of_level(Node *node, int levelsup)
Definition: rewriteManip.c:85
int locate_windowfunc(Node *node)
Definition: rewriteManip.c:253
#define BTLessStrategyNumber
Definition: stratnum.h:29
union ValUnion val
Definition: parsenodes.h:362
ParseLoc location
Definition: parsenodes.h:364
char * aliasname
Definition: primnodes.h:50
List * colnames
Definition: primnodes.h:51
ParseLoc location
Definition: parsenodes.h:295
List * fields
Definition: parsenodes.h:294
List * content
Definition: parsenodes.h:1513
ParseLoc location
Definition: parsenodes.h:1514
Node * expr
Definition: parsenodes.h:784
SortByDir ordering
Definition: parsenodes.h:789
SortByNulls nulls_ordering
Definition: parsenodes.h:790
List * opclass
Definition: parsenodes.h:787
char * name
Definition: parsenodes.h:783
List * collation
Definition: parsenodes.h:786
char * conname
Definition: parsenodes.h:1614
List * indexElems
Definition: parsenodes.h:1612
Node * whereClause
Definition: parsenodes.h:1613
Definition: value.h:29
Definition: pg_list.h:54
Definition: nodes.h:129
NodeTag type
Definition: nodes.h:130
InferClause * infer
Definition: parsenodes.h:1628
OnConflictAction action
Definition: parsenodes.h:1627
AttrNumber p_varattno
Definition: parse_node.h:322
AttrNumber p_varattnosyn
Definition: parse_node.h:327
RangeTblEntry * p_rte
Definition: parse_node.h:287
ParseNamespaceColumn * p_nscolumns
Definition: parse_node.h:291
RTEPermissionInfo * p_perminfo
Definition: parse_node.h:289
bool p_hasWindowFuncs
Definition: parse_node.h:224
ParseNamespaceItem * p_target_nsitem
Definition: parse_node.h:208
ParseExprKind p_expr_kind
Definition: parse_node.h:211
List * p_nullingrels
Definition: parse_node.h:198
List * p_namespace
Definition: parse_node.h:201
List * p_joinexprs
Definition: parse_node.h:197
Relation p_target_relation
Definition: parse_node.h:207
Node * p_last_srf
Definition: parse_node.h:229
List * p_joinlist
Definition: parse_node.h:199
bool p_lateral_active
Definition: parse_node.h:203
List * p_rtable
Definition: parse_node.h:194
bool p_hasAggs
Definition: parse_node.h:223
CmdType commandType
Definition: parsenodes.h:121
Bitmapset * selectedCols
Definition: parsenodes.h:1297
AclMode requiredPerms
Definition: parsenodes.h:1295
bool is_rowsfrom
Definition: parsenodes.h:642
List * coldeflist
Definition: parsenodes.h:645
List * functions
Definition: parsenodes.h:643
Node * subquery
Definition: parsenodes.h:619
Alias * alias
Definition: parsenodes.h:620
ParseLoc location
Definition: parsenodes.h:682
TypeName * typeName
Definition: parsenodes.h:677
List * namespaces
Definition: parsenodes.h:661
Node * docexpr
Definition: parsenodes.h:659
ParseLoc location
Definition: parsenodes.h:664
Node * rowexpr
Definition: parsenodes.h:660
List * columns
Definition: parsenodes.h:662
Alias * alias
Definition: parsenodes.h:663
ParseLoc location
Definition: parsenodes.h:702
struct TableSampleClause * tablesample
Definition: parsenodes.h:1108
RTEKind rtekind
Definition: parsenodes.h:1057
char * relname
Definition: primnodes.h:82
bool inh
Definition: primnodes.h:85
Alias * alias
Definition: primnodes.h:91
char * schemaname
Definition: primnodes.h:79
Node * val
Definition: parsenodes.h:519
ParseLoc location
Definition: parsenodes.h:520
char * name
Definition: parsenodes.h:517
List * args
Definition: primnodes.h:1411
SortByNulls sortby_nulls
Definition: parsenodes.h:548
Node * node
Definition: parsenodes.h:546
List * useOp
Definition: parsenodes.h:549
SortByDir sortby_dir
Definition: parsenodes.h:547
ParseLoc location
Definition: parsenodes.h:550
Index tleSortGroupRef
Definition: parsenodes.h:1442
Definition: value.h:64
ParseLoc location
Definition: primnodes.h:145
Node * docexpr
Definition: primnodes.h:119
Node * rowexpr
Definition: primnodes.h:121
List * colexprs
Definition: primnodes.h:131
TableFuncType functype
Definition: primnodes.h:113
Expr * expr
Definition: primnodes.h:2192
Index ressortgroupref
Definition: primnodes.h:2198
List * parameterTypes
Definition: tsmapi.h:61
bool repeatable_across_queries
Definition: tsmapi.h:64
bool setof
Definition: parsenodes.h:270
Definition: primnodes.h:248
Node * startOffset
Definition: parsenodes.h:1550
List * partitionClause
Definition: parsenodes.h:1546
Node * endOffset
Definition: parsenodes.h:1551
List * orderClause
Definition: parsenodes.h:1548
List * orderClause
Definition: parsenodes.h:567
ParseLoc location
Definition: parsenodes.h:571
List * partitionClause
Definition: parsenodes.h:566
Node * startOffset
Definition: parsenodes.h:569
char * refname
Definition: parsenodes.h:565
Node * endOffset
Definition: parsenodes.h:570
int frameOptions
Definition: parsenodes.h:568
char * name
Definition: parsenodes.h:564
CatCTup * members[FLEXIBLE_ARRAY_MEMBER]
Definition: catcache.h:180
int n_members
Definition: catcache.h:178
HeapTupleData tuple
Definition: catcache.h:123
#define SearchSysCacheList2(cacheId, key1, key2)
Definition: syscache.h:124
void table_close(Relation relation, LOCKMODE lockmode)
Definition: table.c:126
TsmRoutine * GetTsmRoutine(Oid tsmhandler)
Definition: tablesample.c:27
TargetEntry * get_sortgroupref_tle(Index sortref, List *targetList)
Definition: tlist.c:345
Node * get_sortgroupclause_expr(SortGroupClause *sgClause, List *targetList)
Definition: tlist.c:379
TargetEntry * get_sortgroupclause_tle(SortGroupClause *sgClause, List *targetList)
Definition: tlist.c:367
String * makeString(char *str)
Definition: value.c:63
#define intVal(v)
Definition: value.h:79
#define strVal(v)
Definition: value.h:82
bool contain_vars_of_level(Node *node, int levelsup)
Definition: var.c:441
int locate_var_of_level(Node *node, int levelsup)
Definition: var.c:509
const char * name