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 1.85 1998/09/01 04:30:15 momjian 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
 273                  * attrs: have to shorter 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                                 if (--i <= 0)
 283                                         break;
 284                         }
 285                         freeList(lnext(extrl));
 286                         lnext(extrl) = NIL;
 287                 }
 288
 289                 while (ndef-- > 0)
 290                 {
 291                         List       *tl;
 292                         Ident      *id;
 293                         TargetEntry *te;
 294
 295                         foreach(tl, icolumns)
 296                         {
 297                                 id = (Ident *) lfirst(tl);
 298                                 if (!namestrcmp(&(att[defval[ndef].adnum - 1]->attname), id->name))
 299                                         break;
 300                         }
 301                         if (tl != NIL)          /* something given for this attr */
 302                                 continue;
 303
 304                         /*
 305                          * Nothing given for this attr with DEFAULT expr, so add new
 306                          * TargetEntry to qry->targetList. Note, that we set resno to
 307                          * defval[ndef].adnum: it's what
 308                          * transformTargetList()->make_targetlist_expr() does for
 309                          * INSERT ... SELECT. But for INSERT ... VALUES
 310                          * pstate->p_last_resno is used. It doesn't matter for
 311                          * "normal" using (planner creates proper target list in
 312                          * preptlist.c), but may break RULEs in some way. It seems
 313                          * better to create proper target list here...
 314                          */
 315                         te = makeTargetEntry(makeResdom(defval[ndef].adnum,
 316                                                                    att[defval[ndef].adnum - 1]->atttypid,
 317                                                                   att[defval[ndef].adnum - 1]->atttypmod,
 318                            pstrdup(nameout(&(att[defval[ndef].adnum - 1]->attname))),
 319                                                                                         0, 0, 0),
 320                                                           (Node *) stringToNode(defval[ndef].adbin));
 321                         qry->targetList = lappend(qry->targetList, te);
 322                 }
 323         }
 324
 325         /* fix where clause */
 326         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 327
 328         /*
 329          * The havingQual has a similar meaning as "qual" in the where
 330          * statement. So we can easily use the code from the "where clause"
 331          * with some additional traversals done in
 332          * .../optimizer/plan/planner.c
 333          */
 334         qry->havingQual = transformWhereClause(pstate, stmt->havingClause);
 335
 336         qry->hasSubLinks = pstate->p_hasSubLinks;
 337
 338         /* now the range table will not change */
 339         qry->rtable = pstate->p_rtable;
 340         qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
 341
 342         qry->groupClause = transformGroupClause(pstate,
 343                                                                                         stmt->groupClause,
 344                                                                                         qry->targetList);
 345
 346         /* fix order clause */
 347         qry->sortClause = transformSortClause(pstate,
 348                                                                                   NIL,
 349                                                                                   NIL,
 350                                                                                   qry->targetList,
 351                                                                                   qry->uniqueFlag);
 352
 353         qry->hasAggs = pstate->p_hasAggs;
 354         if (pstate->p_hasAggs)
 355                 parseCheckAggregates(pstate, qry);
 356
 357         /*
 358          * The INSERT INTO ... SELECT ... could have a UNION in child, so
 359          * unionClause may be false
 360          */
 361         qry->unionall = stmt->unionall;
 362         qry->unionClause = transformUnionClause(stmt->unionClause, qry->targetList);
 363
 364         /*
 365          * If there is a havingQual but there are no aggregates, then there is
 366          * something wrong with the query because having must contain
 367          * aggregates in its expressions! Otherwise the query could have been
 368          * formulated using the where clause.
 369          */
 370         if ((qry->hasAggs == false) && (qry->havingQual != NULL))
 371         {
 372                 elog(ERROR, "This is not a valid having query!");
 373                 return (Query *) NIL;
 374         }
 375
 376         return (Query *) qry;
 377 }
 378
 379 /*
 380  *      makeTableName()
 381  *      Create a table name from a list of fields.
 382  */
 383 static char *
 384 makeTableName(void *elem,...)
 385 {
 386         va_list         args;
 387
 388         char       *name;
 389         char            buf[NAMEDATALEN + 1];
 390
 391         buf[0] = '\0';
 392
 393         va_start(args, elem);
 394
 395         name = elem;
 396         while (name != NULL)
 397         {
 398                 /* not enough room for next part? then return nothing */
 399                 if ((strlen(buf) + strlen(name)) >= (sizeof(buf) - 1))
 400                         return NULL;
 401
 402                 if (strlen(buf) > 0)
 403                         strcat(buf, "_");
 404                 strcat(buf, name);
 405
 406                 name = va_arg(args, void *);
 407         }
 408
 409         va_end(args);
 410
 411         name = palloc(strlen(buf) + 1);
 412         strcpy(name, buf);
 413
 414         return name;
 415 }
 416
 417 static char *
 418 CreateIndexName(char *table_name, char *column_name, char *label, List *indices)
 419 {
 420         int                     pass = 0;
 421         char       *iname = NULL;
 422         List       *ilist;
 423         IndexStmt  *index;
 424         char            name2[NAMEDATALEN + 1];
 425
 426         /* use working storage, since we might be trying several possibilities */
 427         strcpy(name2, column_name);
 428         while (iname == NULL)
 429         {
 430                 iname = makeTableName(table_name, name2, label, NULL);
 431                 /* unable to make a name at all? then quit */
 432                 if (iname == NULL)
 433                         break;
 434
 435                 ilist = indices;
 436                 while (ilist != NIL)
 437                 {
 438                         index = lfirst(ilist);
 439                         if (strcasecmp(iname, index->idxname) == 0)
 440                                 break;
 441
 442                         ilist = lnext(ilist);
 443                 }
 444                 /* ran through entire list? then no name conflict found so done */
 445                 if (ilist == NIL)
 446                         break;
 447
 448                 /* the last one conflicted, so try a new name component */
 449                 pfree(iname);
 450                 iname = NULL;
 451                 pass++;
 452                 sprintf(name2, "%s_%d", column_name, (pass + 1));
 453         }
 454
 455         return iname;
 456 }
 457
 458 /*
 459  * transformCreateStmt -
 460  *        transforms the "create table" statement
 461  *        SQL92 allows constraints to be scattered all over, so thumb through
 462  *         the columns and collect all constraints into one place.
 463  *        If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
 464  *         then expand those into multiple IndexStmt blocks.
 465  *        - thomas 1997-12-02
 466  */
 467 static Query *
 468 transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
 469 {
 470         Query      *q;
 471         int                     have_pkey = FALSE;
 472         List       *elements;
 473         Node       *element;
 474         List       *columns;
 475         List       *dlist;
 476         ColumnDef  *column;
 477         List       *constraints,
 478                            *clist;
 479         Constraint *constraint;
 480         List       *keys;
 481         Ident      *key;
 482         List       *ilist = NIL;
 483         IndexStmt  *index;
 484         IndexElem  *iparam;
 485
 486         q = makeNode(Query);
 487         q->commandType = CMD_UTILITY;
 488
 489         elements = stmt->tableElts;
 490         constraints = stmt->constraints;
 491         columns = NIL;
 492         dlist = NIL;
 493
 494         while (elements != NIL)
 495         {
 496                 element = lfirst(elements);
 497                 switch (nodeTag(element))
 498                 {
 499                         case T_ColumnDef:
 500                                 column = (ColumnDef *) element;
 501                                 columns = lappend(columns, column);
 502
 503                                 if (column->is_sequence)
 504                                 {
 505                                         char       *cstring;
 506                                         CreateSeqStmt *sequence;
 507
 508                                         constraint = makeNode(Constraint);
 509                                         constraint->contype = CONSTR_DEFAULT;
 510                                         constraint->name = makeTableName(stmt->relname, column->colname, "seq", NULL);
 511                                         cstring = palloc(9 + strlen(constraint->name) + 2 + 1);
 512                                         strcpy(cstring, "nextval('");
 513                                         strcat(cstring, constraint->name);
 514                                         strcat(cstring, "')");
 515                                         constraint->def = cstring;
 516                                         constraint->keys = NULL;
 517
 518                                         if (column->constraints != NIL)
 519                                                 column->constraints = lappend(column->constraints, constraint);
 520                                         else
 521                                                 column->constraints = lcons(constraint, NIL);
 522
 523                                         sequence = makeNode(CreateSeqStmt);
 524                                         sequence->seqname = pstrdup(constraint->name);
 525                                         sequence->options = NIL;
 526
 527                                         elog(NOTICE, "CREATE TABLE will create implicit sequence %s for SERIAL column %s.%s",
 528                                           sequence->seqname, stmt->relname, column->colname);
 529
 530                                         ilist = lcons(sequence, NIL);
 531
 532                                         constraint = makeNode(Constraint);
 533                                         constraint->contype = CONSTR_UNIQUE;
 534                                         constraint->name = makeTableName(stmt->relname, column->colname, "key", NULL);
 535
 536                                         column->constraints = lappend(column->constraints, constraint);
 537                                 }
 538
 539                                 if (column->constraints != NIL)
 540                                 {
 541                                         clist = column->constraints;
 542                                         while (clist != NIL)
 543                                         {
 544                                                 constraint = lfirst(clist);
 545                                                 switch (constraint->contype)
 546                                                 {
 547                                                         case CONSTR_NOTNULL:
 548                                                                 if (column->is_not_null)
 549                                                                         elog(ERROR, "CREATE TABLE/NOT NULL already specified"
 550                                                                                  " for %s.%s", stmt->relname, column->colname);
 551                                                                 column->is_not_null = TRUE;
 552                                                                 break;
 553
 554                                                         case CONSTR_DEFAULT:
 555                                                                 if (column->defval != NULL)
 556                                                                         elog(ERROR, "CREATE TABLE/DEFAULT multiple values specified"
 557                                                                                  " for %s.%s", stmt->relname, column->colname);
 558                                                                 column->defval = constraint->def;
 559                                                                 break;
 560
 561                                                         case CONSTR_PRIMARY:
 562                                                                 if (constraint->name == NULL)
 563                                                                         constraint->name = makeTableName(stmt->relname, "pkey", NULL);
 564                                                                 if (constraint->keys == NIL)
 565                                                                         constraint->keys = lappend(constraint->keys, column);
 566                                                                 dlist = lappend(dlist, constraint);
 567                                                                 break;
 568
 569                                                         case CONSTR_UNIQUE:
 570                                                                 if (constraint->name == NULL)
 571                                                                         constraint->name = makeTableName(stmt->relname, column->colname, "key", NULL);
 572                                                                 if (constraint->keys == NIL)
 573                                                                         constraint->keys = lappend(constraint->keys, column);
 574                                                                 dlist = lappend(dlist, constraint);
 575                                                                 break;
 576
 577                                                         case CONSTR_CHECK:
 578                                                                 constraints = lappend(constraints, constraint);
 579                                                                 if (constraint->name == NULL)
 580                                                                         constraint->name = makeTableName(stmt->relname, column->colname, NULL);
 581                                                                 break;
 582
 583                                                         default:
 584                                                                 elog(ERROR, "parser: internal error; unrecognized constraint", NULL);
 585                                                                 break;
 586                                                 }
 587                                                 clist = lnext(clist);
 588                                         }
 589                                 }
 590                                 break;
 591
 592                         case T_Constraint:
 593                                 constraint = (Constraint *) element;
 594                                 switch (constraint->contype)
 595                                 {
 596                                         case CONSTR_PRIMARY:
 597                                                 if (constraint->name == NULL)
 598                                                         constraint->name = makeTableName(stmt->relname, "pkey", NULL);
 599                                                 dlist = lappend(dlist, constraint);
 600                                                 break;
 601
 602                                         case CONSTR_UNIQUE:
 603 #if FALSE
 604                                                 if (constraint->name == NULL)
 605                                                         constraint->name = makeTableName(stmt->relname, "key", NULL);
 606 #endif
 607                                                 dlist = lappend(dlist, constraint);
 608                                                 break;
 609
 610                                         case CONSTR_CHECK:
 611                                                 constraints = lappend(constraints, constraint);
 612                                                 break;
 613
 614                                         case CONSTR_NOTNULL:
 615                                         case CONSTR_DEFAULT:
 616                                                 elog(ERROR, "parser: internal error; illegal context for constraint", NULL);
 617                                                 break;
 618                                         default:
 619                                                 elog(ERROR, "parser: internal error; unrecognized constraint", NULL);
 620                                                 break;
 621                                 }
 622                                 break;
 623
 624                         default:
 625                                 elog(ERROR, "parser: internal error; unrecognized node", NULL);
 626                 }
 627
 628                 elements = lnext(elements);
 629         }
 630
 631         stmt->tableElts = columns;
 632         stmt->constraints = constraints;
 633
 634 /* Now run through the "deferred list" to complete the query transformation.
 635  * For PRIMARY KEYs, mark each column as NOT NULL and create an index.
 636  * For UNIQUE, create an index as for PRIMARY KEYS, but do not insist on NOT NULL.
 637  *
 638  * Note that this code does not currently look for all possible redundant cases
 639  *      and either ignore or stop with warning. The create might fail later when
 640  *      names for indices turn out to be redundant, or a user might have specified
 641  *      extra useless indices which might hurt performance. - thomas 1997-12-08
 642  */
 643         while (dlist != NIL)
 644         {
 645                 constraint = lfirst(dlist);
 646                 if (nodeTag(constraint) != T_Constraint)
 647                         elog(ERROR, "parser: internal error; unrecognized deferred node", NULL);
 648
 649                 if (constraint->contype == CONSTR_PRIMARY)
 650                 {
 651                         if (have_pkey)
 652                                 elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple primary keys"
 653                                          " for table %s are not legal", stmt->relname);
 654                         else
 655                                 have_pkey = TRUE;
 656                 }
 657                 else if (constraint->contype != CONSTR_UNIQUE)
 658                         elog(ERROR, "parser: internal error; unrecognized deferred constraint", NULL);
 659
 660                 index = makeNode(IndexStmt);
 661
 662                 index->unique = TRUE;
 663                 if (constraint->name != NULL)
 664                         index->idxname = constraint->name;
 665                 else if (constraint->contype == CONSTR_PRIMARY)
 666                 {
 667                         if (have_pkey)
 668                                 elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple keys for table %s are not legal", stmt->relname);
 669
 670                         have_pkey = TRUE;
 671                         index->idxname = makeTableName(stmt->relname, "pkey", NULL);
 672                 }
 673                 else
 674                         index->idxname = NULL;
 675
 676                 index->relname = stmt->relname;
 677                 index->accessMethod = "btree";
 678                 index->indexParams = NIL;
 679                 index->withClause = NIL;
 680                 index->whereClause = NULL;
 681
 682                 keys = constraint->keys;
 683                 while (keys != NIL)
 684                 {
 685                         key = lfirst(keys);
 686                         columns = stmt->tableElts;
 687                         column = NULL;
 688                         while (columns != NIL)
 689                         {
 690                                 column = lfirst(columns);
 691                                 if (strcasecmp(column->colname, key->name) == 0)
 692                                         break;
 693                                 else
 694                                         column = NULL;
 695                                 columns = lnext(columns);
 696                         }
 697                         if (column == NULL)
 698                                 elog(ERROR, "parser: column '%s' in key does not exist", key->name);
 699
 700                         if (constraint->contype == CONSTR_PRIMARY)
 701                                 column->is_not_null = TRUE;
 702                         iparam = makeNode(IndexElem);
 703                         iparam->name = strcpy(palloc(strlen(column->colname) + 1), column->colname);
 704                         iparam->args = NIL;
 705                         iparam->class = NULL;
 706                         iparam->typename = NULL;
 707                         index->indexParams = lappend(index->indexParams, iparam);
 708
 709                         if (index->idxname == NULL)
 710                                 index->idxname = CreateIndexName(stmt->relname, iparam->name, "key", ilist);
 711
 712                         keys = lnext(keys);
 713                 }
 714
 715                 if (index->idxname == NULL)
 716                         elog(ERROR, "parser: unable to construct implicit index for table %s"
 717                                  "; name too long", stmt->relname);
 718                 else
 719                         elog(NOTICE, "CREATE TABLE/%s will create implicit index %s for table %s",
 720                                  ((constraint->contype == CONSTR_PRIMARY) ? "PRIMARY KEY" : "UNIQUE"),
 721                                  index->idxname, stmt->relname);
 722
 723                 ilist = lappend(ilist, index);
 724                 dlist = lnext(dlist);
 725         }
 726
 727         q->utilityStmt = (Node *) stmt;
 728         extras = ilist;
 729
 730         return q;
 731 }
 732
 733 /*
 734  * transformIndexStmt -
 735  *        transforms the qualification of the index statement
 736  */
 737 static Query *
 738 transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
 739 {
 740         Query      *qry;
 741
 742         qry = makeNode(Query);
 743         qry->commandType = CMD_UTILITY;
 744
 745         /* take care of the where clause */
 746         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 747         qry->hasSubLinks = pstate->p_hasSubLinks;
 748
 749         stmt->rangetable = pstate->p_rtable;
 750
 751         qry->utilityStmt = (Node *) stmt;
 752
 753         return qry;
 754 }
 755
 756 /*
 757  * transformExtendStmt -
 758  *        transform the qualifications of the Extend Index Statement
 759  *
 760  */
 761 static Query *
 762 transformExtendStmt(ParseState *pstate, ExtendStmt *stmt)
 763 {
 764         Query      *qry;
 765
 766         qry = makeNode(Query);
 767         qry->commandType = CMD_UTILITY;
 768
 769         /* take care of the where clause */
 770         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 771         qry->hasSubLinks = pstate->p_hasSubLinks;
 772
 773         stmt->rangetable = pstate->p_rtable;
 774
 775         qry->utilityStmt = (Node *) stmt;
 776         return qry;
 777 }
 778
 779 /*
 780  * transformRuleStmt -
 781  *        transform a Create Rule Statement. The actions is a list of parse
 782  *        trees which is transformed into a list of query trees.
 783  */
 784 static Query *
 785 transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
 786 {
 787         Query      *qry;
 788         Query      *action;
 789         List       *actions;
 790
 791         qry = makeNode(Query);
 792         qry->commandType = CMD_UTILITY;
 793
 794         /*
 795          * 'instead nothing' rules with a qualification need a query a
 796          * rangetable so the rewrite handler can add the negated rule
 797          * qualification to the original query. We create a query with the new
 798          * command type CMD_NOTHING here that is treated special by the
 799          * rewrite system.
 800          */
 801         if (stmt->actions == NIL)
 802         {
 803                 Query      *nothing_qry = makeNode(Query);
 804
 805                 nothing_qry->commandType = CMD_NOTHING;
 806
 807                 addRangeTableEntry(pstate, stmt->object->relname, "*CURRENT*",
 808                                                    FALSE, FALSE);
 809                 addRangeTableEntry(pstate, stmt->object->relname, "*NEW*",
 810                                                    FALSE, FALSE);
 811
 812                 nothing_qry->rtable = pstate->p_rtable;
 813
 814                 stmt->actions = lappend(NIL, nothing_qry);
 815         }
 816
 817         actions = stmt->actions;
 818
 819         /*
 820          * transform each statment, like parse_analyze()
 821          */
 822         while (actions != NIL)
 823         {
 824
 825                 /*
 826                  * NOTE: 'CURRENT' must always have a varno equal to 1 and 'NEW'
 827                  * equal to 2.
 828                  */
 829                 addRangeTableEntry(pstate, stmt->object->relname, "*CURRENT*",
 830                                                    FALSE, FALSE);
 831                 addRangeTableEntry(pstate, stmt->object->relname, "*NEW*",
 832                                                    FALSE, FALSE);
 833
 834                 pstate->p_last_resno = 1;
 835                 pstate->p_is_rule = true;               /* for expand all */
 836                 pstate->p_hasAggs = false;
 837
 838                 action = (Query *) lfirst(actions);
 839                 if (action->commandType != CMD_NOTHING)
 840                         lfirst(actions) = transformStmt(pstate, lfirst(actions));
 841                 actions = lnext(actions);
 842         }
 843
 844         /* take care of the where clause */
 845         stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
 846         qry->hasSubLinks = pstate->p_hasSubLinks;
 847
 848         qry->utilityStmt = (Node *) stmt;
 849         return qry;
 850 }
 851
 852
 853 /*
 854  * transformSelectStmt -
 855  *        transforms a Select Statement
 856  *
 857  */
 858 static Query *
 859 transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
 860 {
 861         Query      *qry = makeNode(Query);
 862
 863         qry->commandType = CMD_SELECT;
 864
 865         /* set up a range table */
 866         makeRangeTable(pstate, NULL, stmt->fromClause);
 867
 868         qry->uniqueFlag = stmt->unique;
 869
 870         qry->into = stmt->into;
 871         qry->isPortal = FALSE;
 872
 873         qry->targetList = transformTargetList(pstate, stmt->targetList);
 874
 875         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 876
 877         /*
 878          * The havingQual has a similar meaning as "qual" in the where
 879          * statement. So we can easily use the code from the "where clause"
 880          * with some additional traversals done in
 881          * .../optimizer/plan/planner.c
 882          */
 883         qry->havingQual = transformWhereClause(pstate, stmt->havingClause);
 884
 885         qry->hasSubLinks = pstate->p_hasSubLinks;
 886
 887         qry->sortClause = transformSortClause(pstate,
 888                                                                                   stmt->sortClause,
 889                                                                                   NIL,
 890                                                                                   qry->targetList,
 891                                                                                   qry->uniqueFlag);
 892
 893         qry->groupClause = transformGroupClause(pstate,
 894                                                                                         stmt->groupClause,
 895                                                                                         qry->targetList);
 896         qry->rtable = pstate->p_rtable;
 897
 898         qry->hasAggs = pstate->p_hasAggs;
 899         if (pstate->p_hasAggs)
 900                 parseCheckAggregates(pstate, qry);
 901
 902         /*
 903          * The INSERT INTO ... SELECT ... could have a UNION in child, so
 904          * unionClause may be false
 905          */
 906         qry->unionall = stmt->unionall;
 907         qry->unionClause = transformUnionClause(stmt->unionClause, qry->targetList);
 908
 909         /*
 910          * If there is a havingQual but there are no aggregates, then there is
 911          * something wrong with the query because having must contain
 912          * aggregates in its expressions! Otherwise the query could have been
 913          * formulated using the where clause.
 914          */
 915         if ((qry->hasAggs == false) && (qry->havingQual != NULL))
 916         {
 917                 elog(ERROR, "This is not a valid having query!");
 918                 return (Query *) NIL;
 919         }
 920
 921         return (Query *) qry;
 922 }
 923
 924 /*
 925  * transformUpdateStmt -
 926  *        transforms an update statement
 927  *
 928  */
 929 static Query *
 930 transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
 931 {
 932         Query      *qry = makeNode(Query);
 933
 934         qry->commandType = CMD_UPDATE;
 935         pstate->p_is_update = true;
 936
 937         /*
 938          * the FROM clause is non-standard SQL syntax. We used to be able to
 939          * do this with REPLACE in POSTQUEL so we keep the feature.
 940          */
 941         makeRangeTable(pstate, stmt->relname, stmt->fromClause);
 942
 943         qry->targetList = transformTargetList(pstate, stmt->targetList);
 944
 945         qry->qual = transformWhereClause(pstate, stmt->whereClause);
 946         qry->hasSubLinks = pstate->p_hasSubLinks;
 947
 948         qry->rtable = pstate->p_rtable;
 949
 950         qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
 951
 952         qry->hasAggs = pstate->p_hasAggs;
 953         if (pstate->p_hasAggs)
 954                 parseCheckAggregates(pstate, qry);
 955
 956         return (Query *) qry;
 957 }
 958
 959 /*
 960  * transformCursorStmt -
 961  *        transform a Create Cursor Statement
 962  *
 963  */
 964 static Query *
 965 transformCursorStmt(ParseState *pstate, SelectStmt *stmt)
 966 {
 967         Query      *qry;
 968
 969         qry = transformSelectStmt(pstate, stmt);
 970
 971         qry->into = stmt->portalname;
 972         qry->isPortal = TRUE;
 973         qry->isBinary = stmt->binary;           /* internal portal */
 974
 975         return qry;
 976 }