src/backend/parser/analyze.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * analyze.c--
   4  *        transform the parse tree into a query tree
   5  *
   6  * Copyright (c) 1994, Regents of the University of California
   7  *
   8  *
   9  * IDENTIFICATION
  10  *        $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.86 1998/09/03 14:21:06 thomas Exp $
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <stdarg.h>
  18 #include <string.h>
  19
  20 #include "postgres.h"
  21 #include "access/heapam.h"
  22 #include "nodes/makefuncs.h"
  23 #include "nodes/memnodes.h"
  24 #include "nodes/pg_list.h"
  25 #include "parser/analyze.h"
  26 #include "parser/parse_agg.h"
  27 #include "parser/parse_clause.h"
  28 #include "parser/parse_node.h"
  29 #include "parser/parse_relation.h"
  30 #include "parser/parse_target.h"
  31 #include "utils/builtins.h"
  32 #include "utils/mcxt.h"
  33 #ifdef PARSEDEBUG
  34 #include "nodes/print.h"
  35 #endif
  36
  37 static Query *transformStmt(ParseState *pstate, Node *stmt);
  38 static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
  39 static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt);
  40 static Query *transformIndexStmt(ParseState *pstate, IndexStmt *stmt);
  41 static Query *transformExtendStmt(ParseState *pstate, ExtendStmt *stmt);
  42 static Query *transformRuleStmt(ParseState *query, RuleStmt *stmt);
  43 static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
  44 static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
  45 static Query *transformCursorStmt(ParseState *pstate, SelectStmt *stmt);
  46 static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt);
  47
  48 List       *extras = NIL;
  49
  50 /*
  51  * parse_analyze -
  52  *        analyze a list of parse trees and transform them if necessary.
  53  *
  54  * Returns a list of transformed parse trees. Optimizable statements are
  55  * all transformed to Query while the rest stays the same.
  56  *
  57  */
  58 QueryTreeList *
  59 parse_analyze(List *pl, ParseState *parentParseState)
  60 {
  61         QueryTreeList *result;
  62         ParseState *pstate;
  63         int                     i = 0;
  64
  65         result = malloc(sizeof(QueryTreeList));
  66         result->len = length(pl);
  67         result->qtrees = (Query **) malloc(result->len * sizeof(Query *));
  68
  69         while (pl != NIL)
  70         {
  71 #ifdef PARSEDEBUG
  72                 elog(DEBUG, "parse tree from yacc:\n---\n%s\n---\n", nodeToString(lfirst(pl)));
  73 #endif
  74
  75                 pstate = make_parsestate(parentParseState);
  76                 result->qtrees[i++] = transformStmt(pstate, lfirst(pl));
  77                 if (pstate->p_target_relation != NULL)
  78                         heap_close(pstate->p_target_relation);
  79
  80                 if (extras != NIL)
  81                 {
  82                         result->len += length(extras);
  83                         result->qtrees = (Query **) realloc(result->qtrees, result->len * sizeof(Query *));
  84                         while (extras != NIL)
  85                         {
  86                                 result->qtrees[i++] = transformStmt(pstate, lfirst(extras));
  87                                 if (pstate->p_target_relation != NULL)
  88                                         heap_close(pstate->p_target_relation);
  89                                 extras = lnext(extras);
  90                         }
  91                 }
  92                 extras = NIL;
  93                 pl = lnext(pl);
  94                 pfree(pstate);
  95         }
  96
  97         return result;
  98 }
  99
 100 /*
 101  * transformStmt -
 102  *        transform a Parse tree. If it is an optimizable statement, turn it
 103  *        into a Query tree.
 104  */
 105 static Query *
 106 transformStmt(ParseState *pstate, Node *parseTree)
 107 {
 108         Query      *result = NULL;
 109
 110         switch (nodeTag(parseTree))
 111         {
 112                         /*------------------------
 113                          *      Non-optimizable statements
 114                          *------------------------
 115                          */
 116                 case T_CreateStmt:
 117                         result = transformCreateStmt(pstate, (CreateStmt *) parseTree);
 118                         break;
 119
 120                 case T_IndexStmt:
 121                         result = transformIndexStmt(pstate, (IndexStmt *) parseTree);
 122                         break;
 123
 124                 case T_ExtendStmt:
 125                         result = transformExtendStmt(pstate, (ExtendStmt *) parseTree);
 126                         break;
 127
 128                 case T_RuleStmt:
 129                         result = transformRuleStmt(pstate, (RuleStmt *) parseTree);
 130                         break;
 131
 132                 case T_ViewStmt:
 133                         {
 134                                 ViewStmt   *n = (ViewStmt *) parseTree;
 135
 136                                 n->query = (Query *) transformStmt(pstate, (Node *) n->query);
 137                                 result = makeNode(Query);
 138                                 result->commandType = CMD_UTILITY;
 139                                 result->utilityStmt = (Node *) n;
 140                         }
 141                         break;
 142
 143                 case T_VacuumStmt:
 144                         {
 145                                 MemoryContext oldcontext;
 146
 147                                 /*
 148                                  * make sure that this Query is allocated in TopMemory
 149                                  * context because vacuum spans transactions and we don't
 150                                  * want to lose the vacuum Query due to end-of-transaction
 151                                  * free'ing
 152                                  */
 153                                 oldcontext = MemoryContextSwitchTo(TopMemoryContext);
 154                                 result = makeNode(Query);
 155                                 result->commandType = CMD_UTILITY;
 156                                 result->utilityStmt = (Node *) parseTree;
 157                                 MemoryContextSwitchTo(oldcontext);
 158                                 break;
 159
 160                         }
 161                 case T_ExplainStmt:
 162                         {
 163                                 ExplainStmt *n = (ExplainStmt *) parseTree;
 164
 165                                 result = makeNode(Query);
 166                                 result->commandType = CMD_UTILITY;
 167                                 n->query = transformStmt(pstate, (Node *) n->query);
 168                                 result->utilityStmt = (Node *) parseTree;
 169                         }
 170                         break;
 171
 172                         /*------------------------
 173                          *      Optimizable statements
 174                          *------------------------
 175                          */
 176                 case T_InsertStmt:
 177                         result = transformInsertStmt(pstate, (InsertStmt *) parseTree);
 178                         break;
 179
 180                 case T_DeleteStmt:
 181                         result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
 182                         break;
 183
 184                 case T_UpdateStmt:
 185                         result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
 186                         break;
 187
 188                 case T_SelectStmt:
 189                         if (!((SelectStmt *) parseTree)->portalname)
 190                                 result = transformSelectStmt(pstate, (SelectStmt *) parseTree);
 191                         else
 192                                 result = transformCursorStmt(pstate, (SelectStmt *) parseTree);
 193                         break;
 194
 195                 default:
 196
 197                         /*
 198                          * other statments don't require any transformation-- just
 199                          * return the original parsetree, yea!
 200                          */
 201                         result = makeNode(Query);
 202                         result->commandType = CMD_UTILITY;
 203                         result->utilityStmt = (Node *) parseTree;
 204                         break;
 205         }
 206         return result;
 207 }
 208
 209 /*
 210  * transformDeleteStmt -
 211  *        transforms a Delete Statement
 212  */
 213 static Query *
 214 transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt)
 215 {
 216         Query      *qry = makeNode(Query);
 217
 218         qry->commandType = CMD_DELETE;
 219
 220         /* set up a range table */
 221         makeRangeTable(pstate, stmt->relname, NULL);
 222
 223         qry->uniqueFlag = NULL;
 224
 225         /* fix where clause */
 226         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 227         qry->hasSubLinks = pstate->p_hasSubLinks;
 228
 229         qry->rtable = pstate->p_rtable;
 230         qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
 231
 232         qry->hasAggs = pstate->p_hasAggs;
 233         if (pstate->p_hasAggs)
 234                 parseCheckAggregates(pstate, qry);
 235
 236         return (Query *) qry;
 237 }
 238
 239 /*
 240  * transformInsertStmt -
 241  *        transform an Insert Statement
 242  */
 243 static Query *
 244 transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
 245 {
 246         Query      *qry = makeNode(Query);      /* make a new query tree */
 247         List       *icolumns;
 248
 249         qry->commandType = CMD_INSERT;
 250         pstate->p_is_insert = true;
 251
 252         /* set up a range table */
 253         makeRangeTable(pstate, stmt->relname, stmt->fromClause);
 254
 255         qry->uniqueFlag = stmt->unique;
 256
 257         /* fix the target list */
 258         icolumns = pstate->p_insert_columns = makeTargetNames(pstate, stmt->cols);
 259
 260         qry->targetList = transformTargetList(pstate, stmt->targetList);
 261
 262         /* DEFAULT handling */
 263         if (length(qry->targetList) < pstate->p_target_relation->rd_att->natts &&
 264                 pstate->p_target_relation->rd_att->constr &&
 265                 pstate->p_target_relation->rd_att->constr->num_defval > 0)
 266         {
 267                 Form_pg_attribute *att = pstate->p_target_relation->rd_att->attrs;
 268                 AttrDefault *defval = pstate->p_target_relation->rd_att->constr->defval;
 269                 int                     ndef = pstate->p_target_relation->rd_att->constr->num_defval;
 270
 271                 /*
 272                  * if stmt->cols == NIL then makeTargetNames returns list of all attrs.
 273                  * May have to shorten icolumns list...
 274                  */
 275                 if (stmt->cols == NIL)
 276                 {
 277                         List       *extrl;
 278                         int                     i = length(qry->targetList);
 279
 280                         foreach(extrl, icolumns)
 281                         {
 282                                 /*
 283                                  * decrements first, so if we started with zero items
 284                                  * it will now be negative
 285                                  */
 286                                 if (--i <= 0)
 287                                         break;
 288                         }
 289                         /*
 290                          * this an index into the targetList,
 291                          * so make sure we had one to start...
 292                          */
 293                         if (i >= 0)
 294                         {
 295                                 freeList(lnext(extrl));
 296                                 lnext(extrl) = NIL;
 297                         }
 298                         else
 299                         {
 300                                 icolumns = NIL;
 301                         }
 302                 }
 303
 304                 while (ndef-- > 0)
 305                 {
 306                         List       *tl;
 307                         Ident      *id;
 308                         TargetEntry *te;
 309
 310                         foreach(tl, icolumns)
 311                         {
 312                                 id = (Ident *) lfirst(tl);
 313                                 if (namestrcmp(&(att[defval[ndef].adnum - 1]->attname), id->name) == 0)
 314                                         break;
 315                         }
 316                         if (tl != NIL)          /* something given for this attr */
 317                                 continue;
 318
 319                         /*
 320                          * Nothing given for this attr with DEFAULT expr, so add new
 321                          * TargetEntry to qry->targetList. Note, that we set resno to
 322                          * defval[ndef].adnum: it's what
 323                          * transformTargetList()->make_targetlist_expr() does for
 324                          * INSERT ... SELECT. But for INSERT ... VALUES
 325                          * pstate->p_last_resno is used. It doesn't matter for
 326                          * "normal" using (planner creates proper target list in
 327                          * preptlist.c), but may break RULEs in some way. It seems
 328                          * better to create proper target list here...
 329                          */
 330                         te = makeTargetEntry(makeResdom(defval[ndef].adnum,
 331                                                                    att[defval[ndef].adnum - 1]->atttypid,
 332                                                                   att[defval[ndef].adnum - 1]->atttypmod,
 333                            pstrdup(nameout(&(att[defval[ndef].adnum - 1]->attname))),
 334                                                                                         0, 0, 0),
 335                                                           (Node *) stringToNode(defval[ndef].adbin));
 336                         qry->targetList = lappend(qry->targetList, te);
 337                 }
 338         }
 339
 340         /* fix where clause */
 341         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 342
 343         /*
 344          * The havingQual has a similar meaning as "qual" in the where
 345          * statement. So we can easily use the code from the "where clause"
 346          * with some additional traversals done in
 347          * .../optimizer/plan/planner.c
 348          */
 349         qry->havingQual = transformWhereClause(pstate, stmt->havingClause);
 350
 351         qry->hasSubLinks = pstate->p_hasSubLinks;
 352
 353         /* now the range table will not change */
 354         qry->rtable = pstate->p_rtable;
 355         qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
 356
 357         qry->groupClause = transformGroupClause(pstate,
 358                                                                                         stmt->groupClause,
 359                                                                                         qry->targetList);
 360
 361         /* fix order clause */
 362         qry->sortClause = transformSortClause(pstate,
 363                                                                                   NIL,
 364                                                                                   NIL,
 365                                                                                   qry->targetList,
 366                                                                                   qry->uniqueFlag);
 367
 368         qry->hasAggs = pstate->p_hasAggs;
 369         if (pstate->p_hasAggs)
 370                 parseCheckAggregates(pstate, qry);
 371
 372         /*
 373          * The INSERT INTO ... SELECT ... could have a UNION in child, so
 374          * unionClause may be false
 375          */
 376         qry->unionall = stmt->unionall;
 377         qry->unionClause = transformUnionClause(stmt->unionClause, qry->targetList);
 378
 379         /*
 380          * If there is a havingQual but there are no aggregates, then there is
 381          * something wrong with the query because having must contain
 382          * aggregates in its expressions! Otherwise the query could have been
 383          * formulated using the where clause.
 384          */
 385         if ((qry->hasAggs == false) && (qry->havingQual != NULL))
 386         {
 387                 elog(ERROR, "This is not a valid having query!");
 388                 return (Query *) NIL;
 389         }
 390
 391         return (Query *) qry;
 392 }
 393
 394 /*
 395  *      makeTableName()
 396  *      Create a table name from a list of fields.
 397  */
 398 static char *
 399 makeTableName(void *elem,...)
 400 {
 401         va_list         args;
 402
 403         char       *name;
 404         char            buf[NAMEDATALEN + 1];
 405
 406         buf[0] = '\0';
 407
 408         va_start(args, elem);
 409
 410         name = elem;
 411         while (name != NULL)
 412         {
 413                 /* not enough room for next part? then return nothing */
 414                 if ((strlen(buf) + strlen(name)) >= (sizeof(buf) - 1))
 415                         return NULL;
 416
 417                 if (strlen(buf) > 0)
 418                         strcat(buf, "_");
 419                 strcat(buf, name);
 420
 421                 name = va_arg(args, void *);
 422         }
 423
 424         va_end(args);
 425
 426         name = palloc(strlen(buf) + 1);
 427         strcpy(name, buf);
 428
 429         return name;
 430 }
 431
 432 static char *
 433 CreateIndexName(char *table_name, char *column_name, char *label, List *indices)
 434 {
 435         int                     pass = 0;
 436         char       *iname = NULL;
 437         List       *ilist;
 438         IndexStmt  *index;
 439         char            name2[NAMEDATALEN + 1];
 440
 441         /* use working storage, since we might be trying several possibilities */
 442         strcpy(name2, column_name);
 443         while (iname == NULL)
 444         {
 445                 iname = makeTableName(table_name, name2, label, NULL);
 446                 /* unable to make a name at all? then quit */
 447                 if (iname == NULL)
 448                         break;
 449
 450                 ilist = indices;
 451                 while (ilist != NIL)
 452                 {
 453                         index = lfirst(ilist);
 454                         if (strcasecmp(iname, index->idxname) == 0)
 455                                 break;
 456
 457                         ilist = lnext(ilist);
 458                 }
 459                 /* ran through entire list? then no name conflict found so done */
 460                 if (ilist == NIL)
 461                         break;
 462
 463                 /* the last one conflicted, so try a new name component */
 464                 pfree(iname);
 465                 iname = NULL;
 466                 pass++;
 467                 sprintf(name2, "%s_%d", column_name, (pass + 1));
 468         }
 469
 470         return iname;
 471 }
 472
 473 /*
 474  * transformCreateStmt -
 475  *        transforms the "create table" statement
 476  *        SQL92 allows constraints to be scattered all over, so thumb through
 477  *         the columns and collect all constraints into one place.
 478  *        If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
 479  *         then expand those into multiple IndexStmt blocks.
 480  *        - thomas 1997-12-02
 481  */
 482 static Query *
 483 transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
 484 {
 485         Query      *q;
 486         int                     have_pkey = FALSE;
 487         List       *elements;
 488         Node       *element;
 489         List       *columns;
 490         List       *dlist;
 491         ColumnDef  *column;
 492         List       *constraints,
 493                            *clist;
 494         Constraint *constraint;
 495         List       *keys;
 496         Ident      *key;
 497         List       *ilist = NIL;
 498         IndexStmt  *index;
 499         IndexElem  *iparam;
 500
 501         q = makeNode(Query);
 502         q->commandType = CMD_UTILITY;
 503
 504         elements = stmt->tableElts;
 505         constraints = stmt->constraints;
 506         columns = NIL;
 507         dlist = NIL;
 508
 509         while (elements != NIL)
 510         {
 511                 element = lfirst(elements);
 512                 switch (nodeTag(element))
 513                 {
 514                         case T_ColumnDef:
 515                                 column = (ColumnDef *) element;
 516                                 columns = lappend(columns, column);
 517
 518                                 if (column->is_sequence)
 519                                 {
 520                                         char       *cstring;
 521                                         CreateSeqStmt *sequence;
 522
 523                                         constraint = makeNode(Constraint);
 524                                         constraint->contype = CONSTR_DEFAULT;
 525                                         constraint->name = makeTableName(stmt->relname, column->colname, "seq", NULL);
 526                                         cstring = palloc(9 + strlen(constraint->name) + 2 + 1);
 527                                         strcpy(cstring, "nextval('");
 528                                         strcat(cstring, constraint->name);
 529                                         strcat(cstring, "')");
 530                                         constraint->def = cstring;
 531                                         constraint->keys = NULL;
 532
 533                                         if (column->constraints != NIL)
 534                                                 column->constraints = lappend(column->constraints, constraint);
 535                                         else
 536                                                 column->constraints = lcons(constraint, NIL);
 537
 538                                         sequence = makeNode(CreateSeqStmt);
 539                                         sequence->seqname = pstrdup(constraint->name);
 540                                         sequence->options = NIL;
 541
 542                                         elog(NOTICE, "CREATE TABLE will create implicit sequence %s for SERIAL column %s.%s",
 543                                           sequence->seqname, stmt->relname, column->colname);
 544
 545                                         ilist = lcons(sequence, NIL);
 546
 547                                         constraint = makeNode(Constraint);
 548                                         constraint->contype = CONSTR_UNIQUE;
 549                                         constraint->name = makeTableName(stmt->relname, column->colname, "key", NULL);
 550
 551                                         column->constraints = lappend(column->constraints, constraint);
 552                                 }
 553
 554                                 if (column->constraints != NIL)
 555                                 {
 556                                         clist = column->constraints;
 557                                         while (clist != NIL)
 558                                         {
 559                                                 constraint = lfirst(clist);
 560                                                 switch (constraint->contype)
 561                                                 {
 562                                                         case CONSTR_NOTNULL:
 563                                                                 if (column->is_not_null)
 564                                                                         elog(ERROR, "CREATE TABLE/NOT NULL already specified"
 565                                                                                  " for %s.%s", stmt->relname, column->colname);
 566                                                                 column->is_not_null = TRUE;
 567                                                                 break;
 568
 569                                                         case CONSTR_DEFAULT:
 570                                                                 if (column->defval != NULL)
 571                                                                         elog(ERROR, "CREATE TABLE/DEFAULT multiple values specified"
 572                                                                                  " for %s.%s", stmt->relname, column->colname);
 573                                                                 column->defval = constraint->def;
 574                                                                 break;
 575
 576                                                         case CONSTR_PRIMARY:
 577                                                                 if (constraint->name == NULL)
 578                                                                         constraint->name = makeTableName(stmt->relname, "pkey", NULL);
 579                                                                 if (constraint->keys == NIL)
 580                                                                         constraint->keys = lappend(constraint->keys, column);
 581                                                                 dlist = lappend(dlist, constraint);
 582                                                                 break;
 583
 584                                                         case CONSTR_UNIQUE:
 585                                                                 if (constraint->name == NULL)
 586                                                                         constraint->name = makeTableName(stmt->relname, column->colname, "key", NULL);
 587                                                                 if (constraint->keys == NIL)
 588                                                                         constraint->keys = lappend(constraint->keys, column);
 589                                                                 dlist = lappend(dlist, constraint);
 590                                                                 break;
 591
 592                                                         case CONSTR_CHECK:
 593                                                                 constraints = lappend(constraints, constraint);
 594                                                                 if (constraint->name == NULL)
 595                                                                         constraint->name = makeTableName(stmt->relname, column->colname, NULL);
 596                                                                 break;
 597
 598                                                         default:
 599                                                                 elog(ERROR, "parser: internal error; unrecognized constraint", NULL);
 600                                                                 break;
 601                                                 }
 602                                                 clist = lnext(clist);
 603                                         }
 604                                 }
 605                                 break;
 606
 607                         case T_Constraint:
 608                                 constraint = (Constraint *) element;
 609                                 switch (constraint->contype)
 610                                 {
 611                                         case CONSTR_PRIMARY:
 612                                                 if (constraint->name == NULL)
 613                                                         constraint->name = makeTableName(stmt->relname, "pkey", NULL);
 614                                                 dlist = lappend(dlist, constraint);
 615                                                 break;
 616
 617                                         case CONSTR_UNIQUE:
 618 #if FALSE
 619                                                 if (constraint->name == NULL)
 620                                                         constraint->name = makeTableName(stmt->relname, "key", NULL);
 621 #endif
 622                                                 dlist = lappend(dlist, constraint);
 623                                                 break;
 624
 625                                         case CONSTR_CHECK:
 626                                                 constraints = lappend(constraints, constraint);
 627                                                 break;
 628
 629                                         case CONSTR_NOTNULL:
 630                                         case CONSTR_DEFAULT:
 631                                                 elog(ERROR, "parser: internal error; illegal context for constraint", NULL);
 632                                                 break;
 633                                         default:
 634                                                 elog(ERROR, "parser: internal error; unrecognized constraint", NULL);
 635                                                 break;
 636                                 }
 637                                 break;
 638
 639                         default:
 640                                 elog(ERROR, "parser: internal error; unrecognized node", NULL);
 641                 }
 642
 643                 elements = lnext(elements);
 644         }
 645
 646         stmt->tableElts = columns;
 647         stmt->constraints = constraints;
 648
 649 /* Now run through the "deferred list" to complete the query transformation.
 650  * For PRIMARY KEYs, mark each column as NOT NULL and create an index.
 651  * For UNIQUE, create an index as for PRIMARY KEYS, but do not insist on NOT NULL.
 652  *
 653  * Note that this code does not currently look for all possible redundant cases
 654  *      and either ignore or stop with warning. The create might fail later when
 655  *      names for indices turn out to be redundant, or a user might have specified
 656  *      extra useless indices which might hurt performance. - thomas 1997-12-08
 657  */
 658         while (dlist != NIL)
 659         {
 660                 constraint = lfirst(dlist);
 661                 if (nodeTag(constraint) != T_Constraint)
 662                         elog(ERROR, "parser: internal error; unrecognized deferred node", NULL);
 663
 664                 if (constraint->contype == CONSTR_PRIMARY)
 665                 {
 666                         if (have_pkey)
 667                                 elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple primary keys"
 668                                          " for table %s are not legal", stmt->relname);
 669                         else
 670                                 have_pkey = TRUE;
 671                 }
 672                 else if (constraint->contype != CONSTR_UNIQUE)
 673                         elog(ERROR, "parser: internal error; unrecognized deferred constraint", NULL);
 674
 675                 index = makeNode(IndexStmt);
 676
 677                 index->unique = TRUE;
 678                 if (constraint->name != NULL)
 679                         index->idxname = constraint->name;
 680                 else if (constraint->contype == CONSTR_PRIMARY)
 681                 {
 682                         if (have_pkey)
 683                                 elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple keys for table %s are not legal", stmt->relname);
 684
 685                         have_pkey = TRUE;
 686                         index->idxname = makeTableName(stmt->relname, "pkey", NULL);
 687                 }
 688                 else
 689                         index->idxname = NULL;
 690
 691                 index->relname = stmt->relname;
 692                 index->accessMethod = "btree";
 693                 index->indexParams = NIL;
 694                 index->withClause = NIL;
 695                 index->whereClause = NULL;
 696
 697                 keys = constraint->keys;
 698                 while (keys != NIL)
 699                 {
 700                         key = lfirst(keys);
 701                         columns = stmt->tableElts;
 702                         column = NULL;
 703                         while (columns != NIL)
 704                         {
 705                                 column = lfirst(columns);
 706                                 if (strcasecmp(column->colname, key->name) == 0)
 707                                         break;
 708                                 else
 709                                         column = NULL;
 710                                 columns = lnext(columns);
 711                         }
 712                         if (column == NULL)
 713                                 elog(ERROR, "parser: column '%s' in key does not exist", key->name);
 714
 715                         if (constraint->contype == CONSTR_PRIMARY)
 716                                 column->is_not_null = TRUE;
 717                         iparam = makeNode(IndexElem);
 718                         iparam->name = strcpy(palloc(strlen(column->colname) + 1), column->colname);
 719                         iparam->args = NIL;
 720                         iparam->class = NULL;
 721                         iparam->typename = NULL;
 722                         index->indexParams = lappend(index->indexParams, iparam);
 723
 724                         if (index->idxname == NULL)
 725                                 index->idxname = CreateIndexName(stmt->relname, iparam->name, "key", ilist);
 726
 727                         keys = lnext(keys);
 728                 }
 729
 730                 if (index->idxname == NULL)
 731                         elog(ERROR, "parser: unable to construct implicit index for table %s"
 732                                  "; name too long", stmt->relname);
 733                 else
 734                         elog(NOTICE, "CREATE TABLE/%s will create implicit index %s for table %s",
 735                                  ((constraint->contype == CONSTR_PRIMARY) ? "PRIMARY KEY" : "UNIQUE"),
 736                                  index->idxname, stmt->relname);
 737
 738                 ilist = lappend(ilist, index);
 739                 dlist = lnext(dlist);
 740         }
 741
 742         q->utilityStmt = (Node *) stmt;
 743         extras = ilist;
 744
 745         return q;
 746 }
 747
 748 /*
 749  * transformIndexStmt -
 750  *        transforms the qualification of the index statement
 751  */
 752 static Query *
 753 transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
 754 {
 755         Query      *qry;
 756
 757         qry = makeNode(Query);
 758         qry->commandType = CMD_UTILITY;
 759
 760         /* take care of the where clause */
 761         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 762         qry->hasSubLinks = pstate->p_hasSubLinks;
 763
 764         stmt->rangetable = pstate->p_rtable;
 765
 766         qry->utilityStmt = (Node *) stmt;
 767
 768         return qry;
 769 }
 770
 771 /*
 772  * transformExtendStmt -
 773  *        transform the qualifications of the Extend Index Statement
 774  *
 775  */
 776 static Query *
 777 transformExtendStmt(ParseState *pstate, ExtendStmt *stmt)
 778 {
 779         Query      *qry;
 780
 781         qry = makeNode(Query);
 782         qry->commandType = CMD_UTILITY;
 783
 784         /* take care of the where clause */
 785         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 786         qry->hasSubLinks = pstate->p_hasSubLinks;
 787
 788         stmt->rangetable = pstate->p_rtable;
 789
 790         qry->utilityStmt = (Node *) stmt;
 791         return qry;
 792 }
 793
 794 /*
 795  * transformRuleStmt -
 796  *        transform a Create Rule Statement. The actions is a list of parse
 797  *        trees which is transformed into a list of query trees.
 798  */
 799 static Query *
 800 transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
 801 {
 802         Query      *qry;
 803         Query      *action;
 804         List       *actions;
 805
 806         qry = makeNode(Query);
 807         qry->commandType = CMD_UTILITY;
 808
 809         /*
 810          * 'instead nothing' rules with a qualification need a query a
 811          * rangetable so the rewrite handler can add the negated rule
 812          * qualification to the original query. We create a query with the new
 813          * command type CMD_NOTHING here that is treated special by the
 814          * rewrite system.
 815          */
 816         if (stmt->actions == NIL)
 817         {
 818                 Query      *nothing_qry = makeNode(Query);
 819
 820                 nothing_qry->commandType = CMD_NOTHING;
 821
 822                 addRangeTableEntry(pstate, stmt->object->relname, "*CURRENT*",
 823                                                    FALSE, FALSE);
 824                 addRangeTableEntry(pstate, stmt->object->relname, "*NEW*",
 825                                                    FALSE, FALSE);
 826
 827                 nothing_qry->rtable = pstate->p_rtable;
 828
 829                 stmt->actions = lappend(NIL, nothing_qry);
 830         }
 831
 832         actions = stmt->actions;
 833
 834         /*
 835          * transform each statment, like parse_analyze()
 836          */
 837         while (actions != NIL)
 838         {
 839
 840                 /*
 841                  * NOTE: 'CURRENT' must always have a varno equal to 1 and 'NEW'
 842                  * equal to 2.
 843                  */
 844                 addRangeTableEntry(pstate, stmt->object->relname, "*CURRENT*",
 845                                                    FALSE, FALSE);
 846                 addRangeTableEntry(pstate, stmt->object->relname, "*NEW*",
 847                                                    FALSE, FALSE);
 848
 849                 pstate->p_last_resno = 1;
 850                 pstate->p_is_rule = true;               /* for expand all */
 851                 pstate->p_hasAggs = false;
 852
 853                 action = (Query *) lfirst(actions);
 854                 if (action->commandType != CMD_NOTHING)
 855                         lfirst(actions) = transformStmt(pstate, lfirst(actions));
 856                 actions = lnext(actions);
 857         }
 858
 859         /* take care of the where clause */
 860         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 861         qry->hasSubLinks = pstate->p_hasSubLinks;
 862
 863         qry->utilityStmt = (Node *) stmt;
 864         return qry;
 865 }
 866
 867
 868 /*
 869  * transformSelectStmt -
 870  *        transforms a Select Statement
 871  *
 872  */
 873 static Query *
 874 transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
 875 {
 876         Query      *qry = makeNode(Query);
 877
 878         qry->commandType = CMD_SELECT;
 879
 880         /* set up a range table */
 881         makeRangeTable(pstate, NULL, stmt->fromClause);
 882
 883         qry->uniqueFlag = stmt->unique;
 884
 885         qry->into = stmt->into;
 886         qry->isPortal = FALSE;
 887
 888         qry->targetList = transformTargetList(pstate, stmt->targetList);
 889
 890         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 891
 892         /*
 893          * The havingQual has a similar meaning as "qual" in the where
 894          * statement. So we can easily use the code from the "where clause"
 895          * with some additional traversals done in
 896          * .../optimizer/plan/planner.c
 897          */
 898         qry->havingQual = transformWhereClause(pstate, stmt->havingClause);
 899
 900         qry->hasSubLinks = pstate->p_hasSubLinks;
 901
 902         qry->sortClause = transformSortClause(pstate,
 903                                                                                   stmt->sortClause,
 904                                                                                   NIL,
 905                                                                                   qry->targetList,
 906                                                                                   qry->uniqueFlag);
 907
 908         qry->groupClause = transformGroupClause(pstate,
 909                                                                                         stmt->groupClause,
 910                                                                                         qry->targetList);
 911         qry->rtable = pstate->p_rtable;
 912
 913         qry->hasAggs = pstate->p_hasAggs;
 914         if (pstate->p_hasAggs)
 915                 parseCheckAggregates(pstate, qry);
 916
 917         /*
 918          * The INSERT INTO ... SELECT ... could have a UNION in child, so
 919          * unionClause may be false
 920          */
 921         qry->unionall = stmt->unionall;
 922         qry->unionClause = transformUnionClause(stmt->unionClause, qry->targetList);
 923
 924         /*
 925          * If there is a havingQual but there are no aggregates, then there is
 926          * something wrong with the query because having must contain
 927          * aggregates in its expressions! Otherwise the query could have been
 928          * formulated using the where clause.
 929          */
 930         if ((qry->hasAggs == false) && (qry->havingQual != NULL))
 931         {
 932                 elog(ERROR, "This is not a valid having query!");
 933                 return (Query *) NIL;
 934         }
 935
 936         return (Query *) qry;
 937 }
 938
 939 /*
 940  * transformUpdateStmt -
 941  *        transforms an update statement
 942  *
 943  */
 944 static Query *
 945 transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
 946 {
 947         Query      *qry = makeNode(Query);
 948
 949         qry->commandType = CMD_UPDATE;
 950         pstate->p_is_update = true;
 951
 952         /*
 953          * the FROM clause is non-standard SQL syntax. We used to be able to
 954          * do this with REPLACE in POSTQUEL so we keep the feature.
 955          */
 956         makeRangeTable(pstate, stmt->relname, stmt->fromClause);
 957
 958         qry->targetList = transformTargetList(pstate, stmt->targetList);
 959
 960         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 961         qry->hasSubLinks = pstate->p_hasSubLinks;
 962
 963         qry->rtable = pstate->p_rtable;
 964
 965         qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
 966
 967         qry->hasAggs = pstate->p_hasAggs;
 968         if (pstate->p_hasAggs)
 969                 parseCheckAggregates(pstate, qry);
 970
 971         return (Query *) qry;
 972 }
 973
 974 /*
 975  * transformCursorStmt -
 976  *        transform a Create Cursor Statement
 977  *
 978  */
 979 static Query *
 980 transformCursorStmt(ParseState *pstate, SelectStmt *stmt)
 981 {
 982         Query      *qry;
 983
 984         qry = transformSelectStmt(pstate, stmt);
 985
 986         qry->into = stmt->portalname;
 987         qry->isPortal = TRUE;
 988         qry->isBinary = stmt->binary;           /* internal portal */
 989
 990         return qry;
 991 }