/*-------------------------------------------------------------------------
*
- * analyze.c--
+ * analyze.c
* transform the parse tree into a query tree
*
* Copyright (c) 1994, Regents of the University of California
*
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.50 1997/11/25 22:00:27 momjian Exp $
+ * $Id: analyze.c,v 1.120 1999/10/03 23:55:30 tgl Exp $
*
*-------------------------------------------------------------------------
*/
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
#include "postgres.h"
#include "access/heapam.h"
+#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
-#include "nodes/memnodes.h"
-#include "nodes/pg_list.h"
+#include "parse.h"
#include "parser/analyze.h"
#include "parser/parse_agg.h"
-#include "parser/parse_node.h"
+#include "parser/parse_clause.h"
#include "parser/parse_relation.h"
#include "parser/parse_target.h"
-#include "parser/parse_clause.h"
#include "utils/builtins.h"
-#include "utils/mcxt.h"
static Query *transformStmt(ParseState *pstate, Node *stmt);
static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
-static Query *transformInsertStmt(ParseState *pstate, AppendStmt *stmt);
+static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt);
static Query *transformIndexStmt(ParseState *pstate, IndexStmt *stmt);
static Query *transformExtendStmt(ParseState *pstate, ExtendStmt *stmt);
static Query *transformRuleStmt(ParseState *query, RuleStmt *stmt);
-static Query *transformSelectStmt(ParseState *pstate, RetrieveStmt *stmt);
-static Query *transformUpdateStmt(ParseState *pstate, ReplaceStmt *stmt);
-static Query *transformCursorStmt(ParseState *pstate, CursorStmt *stmt);
+static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
+static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
+static Query *transformCursorStmt(ParseState *pstate, SelectStmt *stmt);
+static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt);
+
+static void transformForUpdate(Query *qry, List *forUpdate);
+void CheckSelectForUpdate(Query *qry);
+
+/* kluge to return extra info from transformCreateStmt() */
+static List *extras_before;
+static List *extras_after;
/*
* Returns a list of transformed parse trees. Optimizable statements are
* all transformed to Query while the rest stays the same.
*
- * CALLER is responsible for freeing the QueryTreeList* returned
*/
-QueryTreeList *
-parse_analyze(List *pl)
+List *
+parse_analyze(List *pl, ParseState *parentParseState)
{
- QueryTreeList *result;
+ List *result = NIL;
ParseState *pstate;
- int i = 0;
-
- result = malloc(sizeof(QueryTreeList));
- result->len = length(pl);
- result->qtrees = (Query **) malloc(result->len * sizeof(Query *));
+ Query *parsetree;
while (pl != NIL)
{
- pstate = make_parsestate();
- result->qtrees[i++] = transformStmt(pstate, lfirst(pl));
- pl = lnext(pl);
+ extras_before = extras_after = NIL;
+ pstate = make_parsestate(parentParseState);
+
+ parsetree = transformStmt(pstate, lfirst(pl));
if (pstate->p_target_relation != NULL)
- heap_close(pstate->p_target_relation);
- free(pstate);
+ heap_close(pstate->p_target_relation, AccessShareLock);
+ pstate->p_target_relation = NULL;
+ pstate->p_target_rangetblentry = NULL;
+
+ while (extras_before != NIL)
+ {
+ result = lappend(result,
+ transformStmt(pstate, lfirst(extras_before)));
+ if (pstate->p_target_relation != NULL)
+ heap_close(pstate->p_target_relation, AccessShareLock);
+ pstate->p_target_relation = NULL;
+ pstate->p_target_rangetblentry = NULL;
+ extras_before = lnext(extras_before);
+ }
+
+ result = lappend(result, parsetree);
+
+ while (extras_after != NIL)
+ {
+ result = lappend(result,
+ transformStmt(pstate, lfirst(extras_after)));
+ if (pstate->p_target_relation != NULL)
+ heap_close(pstate->p_target_relation, AccessShareLock);
+ pstate->p_target_relation = NULL;
+ pstate->p_target_rangetblentry = NULL;
+ extras_after = lnext(extras_after);
+ }
+
+ pfree(pstate);
+ pl = lnext(pl);
}
return result;
* Non-optimizable statements
*------------------------
*/
+ case T_CreateStmt:
+ result = transformCreateStmt(pstate, (CreateStmt *) parseTree);
+ break;
+
case T_IndexStmt:
result = transformIndexStmt(pstate, (IndexStmt *) parseTree);
break;
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) parseTree;
MemoryContextSwitchTo(oldcontext);
- break;
-
}
+ break;
+
case T_ExplainStmt:
{
ExplainStmt *n = (ExplainStmt *) parseTree;
* Optimizable statements
*------------------------
*/
- case T_AppendStmt:
- result = transformInsertStmt(pstate, (AppendStmt *) parseTree);
+ case T_InsertStmt:
+ result = transformInsertStmt(pstate, (InsertStmt *) parseTree);
break;
case T_DeleteStmt:
result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
break;
- case T_ReplaceStmt:
- result = transformUpdateStmt(pstate, (ReplaceStmt *) parseTree);
- break;
-
- case T_CursorStmt:
- result = transformCursorStmt(pstate, (CursorStmt *) parseTree);
+ case T_UpdateStmt:
+ result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
break;
- case T_RetrieveStmt:
- result = transformSelectStmt(pstate, (RetrieveStmt *) parseTree);
+ case T_SelectStmt:
+ if (!((SelectStmt *) parseTree)->portalname)
+ {
+ result = transformSelectStmt(pstate, (SelectStmt *) parseTree);
+ result->limitOffset = ((SelectStmt *) parseTree)->limitOffset;
+ result->limitCount = ((SelectStmt *) parseTree)->limitCount;
+ }
+ else
+ result = transformCursorStmt(pstate, (SelectStmt *) parseTree);
break;
default:
/*
* other statments don't require any transformation-- just
- * return the original parsetree
+ * return the original parsetree, yea!
*/
result = makeNode(Query);
result->commandType = CMD_UTILITY;
qry->commandType = CMD_DELETE;
/* set up a range table */
- makeRangeTable(pstate, stmt->relname, NULL);
+ makeRangeTable(pstate, NULL, NULL);
+ setTargetTable(pstate, stmt->relname);
qry->uniqueFlag = NULL;
/* fix where clause */
- qry->qual = transformWhereClause(pstate, stmt->whereClause);
+ qry->qual = transformWhereClause(pstate, stmt->whereClause, NULL);
+ qry->hasSubLinks = pstate->p_hasSubLinks;
qry->rtable = pstate->p_rtable;
- qry->resultRelation = refnameRangeTablePosn(pstate->p_rtable, stmt->relname);
+ qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
- /* make sure we don't have aggregates in the where clause */
- if (pstate->p_numAgg > 0)
+ qry->hasAggs = pstate->p_hasAggs;
+ if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
return (Query *) qry;
* transform an Insert Statement
*/
static Query *
-transformInsertStmt(ParseState *pstate, AppendStmt *stmt)
+transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
{
- Query *qry = makeNode(Query); /* make a new query tree */
+ Query *qry = makeNode(Query);
+ Node *fromQual;
List *icolumns;
+ List *tl;
+ TupleDesc rd_att;
qry->commandType = CMD_INSERT;
pstate->p_is_insert = true;
- /* set up a range table */
- makeRangeTable(pstate, stmt->relname, stmt->fromClause);
+ /*----------
+ * Initial processing steps are just like SELECT, which should not
+ * be surprising, since we may be handling an INSERT ... SELECT.
+ * It is important that we finish processing all the SELECT subclauses
+ * before we start doing any INSERT-specific processing; otherwise
+ * the behavior of SELECT within INSERT might be different from a
+ * stand-alone SELECT. (Indeed, Postgres up through 6.5 had bugs of
+ * just that nature...)
+ *----------
+ */
- qry->uniqueFlag = NULL;
+ /* set up a range table --- note INSERT target is not in it yet */
+ makeRangeTable(pstate, stmt->fromClause, &fromQual);
+
+ qry->uniqueFlag = stmt->unique;
- /* fix the target list */
- icolumns = pstate->p_insert_columns = makeTargetNames(pstate, stmt->cols);
-
qry->targetList = transformTargetList(pstate, stmt->targetList);
-
- /* DEFAULT handling */
- if (length(qry->targetList) < pstate->p_target_relation->rd_att->natts &&
- pstate->p_target_relation->rd_att->constr &&
- pstate->p_target_relation->rd_att->constr->num_defval > 0)
+
+ qry->qual = transformWhereClause(pstate, stmt->whereClause, fromQual);
+
+ /* Initial processing of HAVING clause is just like WHERE clause.
+ * Additional work will be done in optimizer/plan/planner.c.
+ */
+ qry->havingQual = transformWhereClause(pstate, stmt->havingClause, NULL);
+
+ qry->groupClause = transformGroupClause(pstate,
+ stmt->groupClause,
+ qry->targetList);
+
+ /* An InsertStmt has no sortClause, but we still call
+ * transformSortClause because it also handles uniqueFlag.
+ */
+ qry->sortClause = transformSortClause(pstate,
+ NIL,
+ qry->targetList,
+ qry->uniqueFlag);
+
+ qry->hasSubLinks = pstate->p_hasSubLinks;
+ qry->hasAggs = pstate->p_hasAggs;
+ if (pstate->p_hasAggs || qry->groupClause)
+ parseCheckAggregates(pstate, qry);
+
+ /*
+ * If there is a havingQual but there are no aggregates, then there is
+ * something wrong with the query because HAVING must contain
+ * aggregates in its expressions! Otherwise the query could have been
+ * formulated using the WHERE clause.
+ */
+ if (qry->havingQual && ! qry->hasAggs)
+ elog(ERROR, "SELECT/HAVING requires aggregates to be valid");
+
+ /*
+ * The INSERT INTO ... SELECT ... could have a UNION in child, so
+ * unionClause may be false
+ */
+ qry->unionall = stmt->unionall;
+
+ /*
+ * Just hand through the unionClause and intersectClause. We will
+ * handle it in the function Except_Intersect_Rewrite()
+ */
+ qry->unionClause = stmt->unionClause;
+ qry->intersectClause = stmt->intersectClause;
+
+ /*
+ * Now we are done with SELECT-like processing, and can get on with
+ * transforming the target list to match the INSERT target columns.
+ *
+ * In particular, it's time to add the INSERT target to the rangetable.
+ * (We didn't want it there until now since it shouldn't be visible in
+ * the SELECT part.)
+ */
+ setTargetTable(pstate, stmt->relname);
+
+ /* now the range table will not change */
+ qry->rtable = pstate->p_rtable;
+ qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
+
+ /* Prepare to assign non-conflicting resnos to resjunk attributes */
+ if (pstate->p_last_resno <= pstate->p_target_relation->rd_rel->relnatts)
+ pstate->p_last_resno = pstate->p_target_relation->rd_rel->relnatts + 1;
+
+ /* Validate stmt->cols list, or build default list if no list given */
+ icolumns = makeTargetNames(pstate, stmt->cols);
+
+ /* Prepare non-junk columns for assignment to target table */
+ foreach(tl, qry->targetList)
{
- AttributeTupleForm *att = pstate->p_target_relation->rd_att->attrs;
- AttrDefault *defval = pstate->p_target_relation->rd_att->constr->defval;
- int ndef = pstate->p_target_relation->rd_att->constr->num_defval;
-
- /*
- * if stmt->cols == NIL then makeTargetNames returns list of all
- * attrs: have to shorter icolumns list...
- */
- if (stmt->cols == NIL)
+ TargetEntry *tle = (TargetEntry *) lfirst(tl);
+ Resdom *resnode = tle->resdom;
+ Ident *id;
+
+ if (resnode->resjunk)
{
- List *extrl;
- int i = length(qry->targetList);
-
- foreach (extrl, icolumns)
- {
- if (--i <= 0)
- break;
- }
- freeList (lnext(extrl));
- lnext(extrl) = NIL;
+ /* Resjunk nodes need no additional processing, but be sure they
+ * have names and resnos that do not match any target columns;
+ * else rewriter or planner might get confused.
+ */
+ resnode->resname = "?resjunk?";
+ resnode->resno = (AttrNumber) pstate->p_last_resno++;
+ continue;
}
-
+ if (icolumns == NIL)
+ elog(ERROR, "INSERT has more expressions than target columns");
+ id = (Ident *) lfirst(icolumns);
+ updateTargetListEntry(pstate, tle, id->name, id->indirection);
+ icolumns = lnext(icolumns);
+ }
+
+ /*
+ * Add targetlist items to assign DEFAULT values to any columns that
+ * have defaults and were not assigned to by the user.
+ * XXX wouldn't it make more sense to do this further downstream,
+ * after the rule rewriter?
+ */
+ rd_att = pstate->p_target_relation->rd_att;
+ if (rd_att->constr && rd_att->constr->num_defval > 0)
+ {
+ Form_pg_attribute *att = rd_att->attrs;
+ AttrDefault *defval = rd_att->constr->defval;
+ int ndef = rd_att->constr->num_defval;
+
while (ndef-- > 0)
{
- List *tl;
- Ident *id;
- TargetEntry *te;
-
- foreach (tl, icolumns)
+ Form_pg_attribute thisatt = att[defval[ndef].adnum - 1];
+ TargetEntry *te;
+
+ foreach(tl, qry->targetList)
{
- id = (Ident *) lfirst(tl);
- if (!namestrcmp(&(att[defval[ndef].adnum - 1]->attname), id->name))
+ TargetEntry *tle = (TargetEntry *) lfirst(tl);
+ Resdom *resnode = tle->resdom;
+
+ if (resnode->resjunk)
+ continue; /* ignore resjunk nodes */
+ if (namestrcmp(&(thisatt->attname), resnode->resname) == 0)
break;
}
- if (tl != NIL) /* something given for this attr */
+ if (tl != NIL) /* found TLE for this attr */
continue;
- /*
- * Nothing given for this attr with DEFAULT expr, so
- * add new TargetEntry to qry->targetList.
- * Note, that we set resno to defval[ndef].adnum:
- * it's what transformTargetList()->make_targetlist_expr()
- * does for INSERT ... SELECT. But for INSERT ... VALUES
- * pstate->p_last_resno is used. It doesn't matter for
- * "normal" using (planner creates proper target list
- * in preptlist.c), but may break RULEs in some way.
- * It seems better to create proper target list here...
+ /*
+ * No user-supplied value, so add a targetentry with DEFAULT expr
+ * and correct data for the target column.
*/
- te = makeNode(TargetEntry);
- te->resdom = makeResdom(defval[ndef].adnum,
- att[defval[ndef].adnum - 1]->atttypid,
- att[defval[ndef].adnum - 1]->attlen,
- pstrdup(nameout(&(att[defval[ndef].adnum - 1]->attname))),
- 0, 0, 0);
- te->fjoin = NULL;
- te->expr = (Node *) stringToNode(defval[ndef].adbin);
- qry->targetList = lappend (qry->targetList, te);
+ te = makeTargetEntry(
+ makeResdom(defval[ndef].adnum,
+ thisatt->atttypid,
+ thisatt->atttypmod,
+ pstrdup(nameout(&(thisatt->attname))),
+ 0, 0, false),
+ stringToNode(defval[ndef].adbin));
+ qry->targetList = lappend(qry->targetList, te);
+ /*
+ * Make sure the value is coerced to the target column type
+ * (might not be right type if it's not a constant!)
+ */
+ updateTargetListEntry(pstate, te, te->resdom->resname, NIL);
}
}
-
- /* fix where clause */
- qry->qual = transformWhereClause(pstate, stmt->whereClause);
- /* now the range table will not change */
- qry->rtable = pstate->p_rtable;
- qry->resultRelation = refnameRangeTablePosn(pstate->p_rtable, stmt->relname);
-
- if (pstate->p_numAgg > 0)
- finalizeAggregates(pstate, qry);
+ if (stmt->forUpdate != NULL)
+ transformForUpdate(qry, stmt->forUpdate);
return (Query *) qry;
}
/*
- * transformIndexStmt -
- * transforms the qualification of the index statement
+ * makeObjectName()
+ *
+ * Create a name for an implicitly created index, sequence, constraint, etc.
+ *
+ * The parameters are: the original table name, the original field name, and
+ * a "type" string (such as "seq" or "pkey"). The field name and/or type
+ * can be NULL if not relevant.
+ *
+ * The result is a palloc'd string.
+ *
+ * The basic result we want is "name1_name2_type", omitting "_name2" or
+ * "_type" when those parameters are NULL. However, we must generate
+ * a name with less than NAMEDATALEN characters! So, we truncate one or
+ * both names if necessary to make a short-enough string. The type part
+ * is never truncated (so it had better be reasonably short).
+ *
+ * To reduce the probability of collisions, we might someday add more
+ * smarts to this routine, like including some "hash" characters computed
+ * from the truncated characters. Currently it seems best to keep it simple,
+ * so that the generated names are easily predictable by a person.
+ */
+static char *
+makeObjectName(char *name1, char *name2, char *typename)
+{
+ char *name;
+ int overhead = 0; /* chars needed for type and underscores */
+ int availchars; /* chars available for name(s) */
+ int name1chars; /* chars allocated to name1 */
+ int name2chars; /* chars allocated to name2 */
+ int ndx;
+
+ name1chars = strlen(name1);
+ if (name2)
+ {
+ name2chars = strlen(name2);
+ overhead++; /* allow for separating underscore */
+ }
+ else
+ name2chars = 0;
+ if (typename)
+ overhead += strlen(typename) + 1;
+
+ availchars = NAMEDATALEN-1 - overhead;
+
+ /* If we must truncate, preferentially truncate the longer name.
+ * This logic could be expressed without a loop, but it's simple and
+ * obvious as a loop.
+ */
+ while (name1chars + name2chars > availchars)
+ {
+ if (name1chars > name2chars)
+ name1chars--;
+ else
+ name2chars--;
+ }
+
+ /* Now construct the string using the chosen lengths */
+ name = palloc(name1chars + name2chars + overhead + 1);
+ strncpy(name, name1, name1chars);
+ ndx = name1chars;
+ if (name2)
+ {
+ name[ndx++] = '_';
+ strncpy(name+ndx, name2, name2chars);
+ ndx += name2chars;
+ }
+ if (typename)
+ {
+ name[ndx++] = '_';
+ strcpy(name+ndx, typename);
+ }
+ else
+ name[ndx] = '\0';
+
+ return name;
+}
+
+static char *
+CreateIndexName(char *table_name, char *column_name, char *label, List *indices)
+{
+ int pass = 0;
+ char *iname = NULL;
+ List *ilist;
+ char typename[NAMEDATALEN];
+
+ /* The type name for makeObjectName is label, or labelN if that's
+ * necessary to prevent collisions among multiple indexes for the same
+ * table. Note there is no check for collisions with already-existing
+ * indexes; this ought to be rethought someday.
+ */
+ strcpy(typename, label);
+
+ for (;;)
+ {
+ iname = makeObjectName(table_name, column_name, typename);
+
+ foreach(ilist, indices)
+ {
+ IndexStmt *index = lfirst(ilist);
+ if (strcasecmp(iname, index->idxname) == 0)
+ break;
+ }
+ /* ran through entire list? then no name conflict found so done */
+ if (ilist == NIL)
+ break;
+
+ /* the last one conflicted, so try a new name component */
+ pfree(iname);
+ sprintf(typename, "%s%d", label, ++pass);
+ }
+
+ return iname;
+}
+
+/*
+ * transformCreateStmt -
+ * transforms the "create table" statement
+ * SQL92 allows constraints to be scattered all over, so thumb through
+ * the columns and collect all constraints into one place.
+ * If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
+ * then expand those into multiple IndexStmt blocks.
+ * - thomas 1997-12-02
*/
static Query *
-transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
+transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
{
Query *q;
+ List *elements;
+ Node *element;
+ List *columns;
+ List *dlist;
+ ColumnDef *column;
+ List *constraints,
+ *clist;
+ Constraint *constraint;
+ List *keys;
+ Ident *key;
+ List *blist = NIL; /* "before list" of things to do before
+ * creating the table */
+ List *ilist = NIL; /* "index list" of things to do after
+ * creating the table */
+ IndexStmt *index,
+ *pkey = NULL;
+ IndexElem *iparam;
q = makeNode(Query);
q->commandType = CMD_UTILITY;
- /* take care of the where clause */
- stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
- stmt->rangetable = pstate->p_rtable;
+ constraints = stmt->constraints;
+ columns = NIL;
+ dlist = NIL;
+
+ /*
+ * Run through each primary element in the table creation clause
+ */
+ foreach(elements, stmt->tableElts)
+ {
+ element = lfirst(elements);
+ switch (nodeTag(element))
+ {
+ case T_ColumnDef:
+ column = (ColumnDef *) element;
+ columns = lappend(columns, column);
+
+ /* Special case SERIAL type? */
+ if (column->is_sequence)
+ {
+ char *sname;
+ char *qstring;
+ A_Const *snamenode;
+ FuncCall *funccallnode;
+ CreateSeqStmt *sequence;
+
+ sname = makeObjectName(stmt->relname, column->colname,
+ "seq");
+ /*
+ * Create an expression tree representing the function
+ * call nextval('"sequencename"')
+ */
+ qstring = palloc(strlen(sname) + 2 + 1);
+ sprintf(qstring, "\"%s\"", sname);
+ snamenode = makeNode(A_Const);
+ snamenode->val.type = T_String;
+ snamenode->val.val.str = qstring;
+ funccallnode = makeNode(FuncCall);
+ funccallnode->funcname = "nextval";
+ funccallnode->args = lcons(snamenode, NIL);
+
+ constraint = makeNode(Constraint);
+ constraint->contype = CONSTR_DEFAULT;
+ constraint->name = sname;
+ constraint->raw_expr = (Node *) funccallnode;
+ constraint->cooked_expr = NULL;
+ constraint->keys = NULL;
+
+ column->constraints = lappend(column->constraints, constraint);
+
+ constraint = makeNode(Constraint);
+ constraint->contype = CONSTR_UNIQUE;
+ constraint->name = makeObjectName(stmt->relname,
+ column->colname,
+ "key");
+ column->constraints = lappend(column->constraints, constraint);
+
+ sequence = makeNode(CreateSeqStmt);
+ sequence->seqname = pstrdup(sname);
+ sequence->options = NIL;
+
+ elog(NOTICE, "CREATE TABLE will create implicit sequence '%s' for SERIAL column '%s.%s'",
+ sequence->seqname, stmt->relname, column->colname);
+
+ blist = lcons(sequence, NIL);
+ }
+
+ /* Process column constraints, if any... */
+ foreach(clist, column->constraints)
+ {
+ constraint = lfirst(clist);
+ switch (constraint->contype)
+ {
+ case CONSTR_NULL:
+
+ /*
+ * We should mark this explicitly, so we
+ * can tell if NULL and NOT NULL are both
+ * specified
+ */
+ if (column->is_not_null)
+ elog(ERROR, "CREATE TABLE/(NOT) NULL conflicting declaration"
+ " for '%s.%s'", stmt->relname, column->colname);
+ column->is_not_null = FALSE;
+ break;
+
+ case CONSTR_NOTNULL:
+ if (column->is_not_null)
+ elog(ERROR, "CREATE TABLE/NOT NULL already specified"
+ " for '%s.%s'", stmt->relname, column->colname);
+ column->is_not_null = TRUE;
+ break;
+
+ case CONSTR_DEFAULT:
+ if (column->raw_default != NULL)
+ elog(ERROR, "CREATE TABLE/DEFAULT multiple values specified"
+ " for '%s.%s'", stmt->relname, column->colname);
+ column->raw_default = constraint->raw_expr;
+ Assert(constraint->cooked_expr == NULL);
+ break;
+
+ case CONSTR_PRIMARY:
+ if (constraint->name == NULL)
+ constraint->name = makeObjectName(stmt->relname, NULL, "pkey");
+ if (constraint->keys == NIL)
+ constraint->keys = lappend(constraint->keys, column);
+ dlist = lappend(dlist, constraint);
+ break;
+
+ case CONSTR_UNIQUE:
+ if (constraint->name == NULL)
+ constraint->name = makeObjectName(stmt->relname, column->colname, "key");
+ if (constraint->keys == NIL)
+ constraint->keys = lappend(constraint->keys, column);
+ dlist = lappend(dlist, constraint);
+ break;
+
+ case CONSTR_CHECK:
+ if (constraint->name == NULL)
+ constraint->name = makeObjectName(stmt->relname, column->colname, NULL);
+ constraints = lappend(constraints, constraint);
+ break;
+
+ default:
+ elog(ERROR, "parser: unrecognized constraint (internal error)", NULL);
+ break;
+ }
+ }
+ break;
+
+ case T_Constraint:
+ constraint = (Constraint *) element;
+ switch (constraint->contype)
+ {
+ case CONSTR_PRIMARY:
+ if (constraint->name == NULL)
+ constraint->name = makeObjectName(stmt->relname, NULL, "pkey");
+ dlist = lappend(dlist, constraint);
+ break;
+
+ case CONSTR_UNIQUE:
+ dlist = lappend(dlist, constraint);
+ break;
+
+ case CONSTR_CHECK:
+ constraints = lappend(constraints, constraint);
+ break;
+
+ case CONSTR_NOTNULL:
+ case CONSTR_DEFAULT:
+ elog(ERROR, "parser: illegal context for constraint (internal error)");
+ break;
+ default:
+ elog(ERROR, "parser: unrecognized constraint (internal error)");
+ break;
+ }
+ break;
+
+ default:
+ elog(ERROR, "parser: unrecognized node (internal error)");
+ }
+ }
+
+ stmt->tableElts = columns;
+ stmt->constraints = constraints;
+
+/* Now run through the "deferred list" to complete the query transformation.
+ * For PRIMARY KEYs, mark each column as NOT NULL and create an index.
+ * For UNIQUE, create an index as for PRIMARY KEYS, but do not insist on NOT NULL.
+ *
+ * Note that this code does not currently look for all possible redundant cases
+ * and either ignore or stop with warning. The create might fail later when
+ * names for indices turn out to be duplicated, or a user might have specified
+ * extra useless indices which might hurt performance. - thomas 1997-12-08
+ */
+ while (dlist != NIL)
+ {
+ constraint = lfirst(dlist);
+ Assert(nodeTag(constraint) == T_Constraint);
+ Assert((constraint->contype == CONSTR_PRIMARY)
+ || (constraint->contype == CONSTR_UNIQUE));
+
+ index = makeNode(IndexStmt);
+
+ index->unique = TRUE;
+ index->primary = (constraint->contype == CONSTR_PRIMARY ? TRUE : FALSE);
+ if (index->primary)
+ {
+ if (pkey != NULL)
+ elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple primary keys"
+ " for table '%s' are not allowed", stmt->relname);
+ pkey = (IndexStmt *) index;
+ }
+
+ if (constraint->name != NULL)
+ index->idxname = pstrdup(constraint->name);
+ else if (constraint->contype == CONSTR_PRIMARY)
+ index->idxname = makeObjectName(stmt->relname, NULL, "pkey");
+ else
+ index->idxname = NULL;
+
+ index->relname = stmt->relname;
+ index->accessMethod = "btree";
+ index->indexParams = NIL;
+ index->withClause = NIL;
+ index->whereClause = NULL;
+
+ keys = constraint->keys;
+ while (keys != NIL)
+ {
+ key = lfirst(keys);
+ columns = stmt->tableElts;
+ column = NULL;
+ while (columns != NIL)
+ {
+ column = lfirst(columns);
+ if (strcasecmp(column->colname, key->name) == 0)
+ break;
+ else
+ column = NULL;
+ columns = lnext(columns);
+ }
+ if (column == NULL)
+ elog(ERROR, "CREATE TABLE column '%s' in key does not exist", key->name);
+
+ if (constraint->contype == CONSTR_PRIMARY)
+ column->is_not_null = TRUE;
+ iparam = makeNode(IndexElem);
+ iparam->name = pstrdup(column->colname);
+ iparam->args = NIL;
+ iparam->class = NULL;
+ iparam->typename = NULL;
+ index->indexParams = lappend(index->indexParams, iparam);
+
+ if (index->idxname == NULL)
+ index->idxname = CreateIndexName(stmt->relname, iparam->name, "key", ilist);
+
+ keys = lnext(keys);
+ }
+
+ if (index->idxname == NULL) /* should not happen */
+ elog(ERROR, "CREATE TABLE: failed to make implicit index name");
+
+ ilist = lappend(ilist, index);
+ dlist = lnext(dlist);
+ }
+
+/* OK, now finally, if there is a primary key, then make sure that there aren't any redundant
+ * unique indices defined on columns. This can arise if someone specifies UNIQUE explicitly
+ * or if a SERIAL column was defined along with a table PRIMARY KEY constraint.
+ * - thomas 1999-05-11
+ */
+ if (pkey != NULL)
+ {
+ dlist = ilist;
+ ilist = NIL;
+ while (dlist != NIL)
+ {
+ List *pcols, *icols;
+ int plen, ilen;
+ int keep = TRUE;
+
+ index = lfirst(dlist);
+ pcols = pkey->indexParams;
+ icols = index->indexParams;
+
+ plen = length(pcols);
+ ilen = length(icols);
+
+ /* Not the same as the primary key? Then we should look... */
+ if ((index != pkey) && (ilen == plen))
+ {
+ keep = FALSE;
+ while ((pcols != NIL) && (icols != NIL))
+ {
+ IndexElem *pcol = lfirst(pcols);
+ IndexElem *icol = lfirst(icols);
+ char *pname = pcol->name;
+ char *iname = icol->name;
+
+ /* different names? then no match... */
+ if (strcmp(iname, pname) != 0)
+ {
+ keep = TRUE;
+ break;
+ }
+ pcols = lnext(pcols);
+ icols = lnext(icols);
+ }
+ }
+
+ if (keep)
+ ilist = lappend(ilist, index);
+ dlist = lnext(dlist);
+ }
+ }
+
+ dlist = ilist;
+ while (dlist != NIL)
+ {
+ index = lfirst(dlist);
+ elog(NOTICE, "CREATE TABLE/%s will create implicit index '%s' for table '%s'",
+ (index->primary ? "PRIMARY KEY" : "UNIQUE"),
+ index->idxname, stmt->relname);
+ dlist = lnext(dlist);
+ }
q->utilityStmt = (Node *) stmt;
+ extras_before = blist;
+ extras_after = ilist;
return q;
+} /* transformCreateStmt() */
+
+/*
+ * transformIndexStmt -
+ * transforms the qualification of the index statement
+ */
+static Query *
+transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
+{
+ Query *qry;
+
+ qry = makeNode(Query);
+ qry->commandType = CMD_UTILITY;
+
+ /* take care of the where clause */
+ stmt->whereClause = transformWhereClause(pstate, stmt->whereClause, NULL);
+ qry->hasSubLinks = pstate->p_hasSubLinks;
+
+ stmt->rangetable = pstate->p_rtable;
+
+ qry->utilityStmt = (Node *) stmt;
+
+ return qry;
}
/*
static Query *
transformExtendStmt(ParseState *pstate, ExtendStmt *stmt)
{
- Query *q;
+ Query *qry;
- q = makeNode(Query);
- q->commandType = CMD_UTILITY;
+ qry = makeNode(Query);
+ qry->commandType = CMD_UTILITY;
/* take care of the where clause */
- stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
+ stmt->whereClause = transformWhereClause(pstate, stmt->whereClause, NULL);
+ qry->hasSubLinks = pstate->p_hasSubLinks;
+
stmt->rangetable = pstate->p_rtable;
- q->utilityStmt = (Node *) stmt;
- return q;
+ qry->utilityStmt = (Node *) stmt;
+ return qry;
}
/*
static Query *
transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
{
- Query *q;
+ Query *qry;
+ Query *action;
List *actions;
- q = makeNode(Query);
- q->commandType = CMD_UTILITY;
+ qry = makeNode(Query);
+ qry->commandType = CMD_UTILITY;
+
+ /*
+ * 'instead nothing' rules with a qualification need a query a
+ * rangetable so the rewrite handler can add the negated rule
+ * qualification to the original query. We create a query with the new
+ * command type CMD_NOTHING here that is treated special by the
+ * rewrite system.
+ */
+ if (stmt->actions == NIL)
+ {
+ Query *nothing_qry = makeNode(Query);
+
+ nothing_qry->commandType = CMD_NOTHING;
+
+ addRangeTableEntry(pstate, stmt->object->relname, "*CURRENT*",
+ FALSE, FALSE);
+ addRangeTableEntry(pstate, stmt->object->relname, "*NEW*",
+ FALSE, FALSE);
+
+ nothing_qry->rtable = pstate->p_rtable;
+
+ stmt->actions = lappend(NIL, nothing_qry);
+ }
actions = stmt->actions;
pstate->p_last_resno = 1;
pstate->p_is_rule = true; /* for expand all */
- pstate->p_numAgg = 0;
- pstate->p_aggs = NULL;
+ pstate->p_hasAggs = false;
- lfirst(actions) = transformStmt(pstate, lfirst(actions));
+ action = (Query *) lfirst(actions);
+ if (action->commandType != CMD_NOTHING)
+ lfirst(actions) = transformStmt(pstate, lfirst(actions));
actions = lnext(actions);
}
/* take care of the where clause */
- stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
+ stmt->whereClause = transformWhereClause(pstate, stmt->whereClause, NULL);
+ qry->hasSubLinks = pstate->p_hasSubLinks;
- q->utilityStmt = (Node *) stmt;
- return q;
+ qry->utilityStmt = (Node *) stmt;
+ return qry;
}
*
*/
static Query *
-transformSelectStmt(ParseState *pstate, RetrieveStmt *stmt)
+transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
{
Query *qry = makeNode(Query);
+ Node *fromQual;
qry->commandType = CMD_SELECT;
/* set up a range table */
- makeRangeTable(pstate, NULL, stmt->fromClause);
+ makeRangeTable(pstate, stmt->fromClause, &fromQual);
qry->uniqueFlag = stmt->unique;
qry->into = stmt->into;
+ qry->isTemp = stmt->istemp;
qry->isPortal = FALSE;
- /* fix the target list */
qry->targetList = transformTargetList(pstate, stmt->targetList);
- /* fix where clause */
- qry->qual = transformWhereClause(pstate, stmt->whereClause);
+ qry->qual = transformWhereClause(pstate, stmt->whereClause, fromQual);
- /* check subselect clause */
- if (stmt->selectClause)
- elog(NOTICE, "UNION not yet supported; using first SELECT only", NULL);
+ /* Initial processing of HAVING clause is just like WHERE clause.
+ * Additional work will be done in optimizer/plan/planner.c.
+ */
+ qry->havingQual = transformWhereClause(pstate, stmt->havingClause, NULL);
- /* check subselect clause */
- if (stmt->havingClause)
- elog(NOTICE, "HAVING not yet supported; ignore clause", NULL);
+ qry->groupClause = transformGroupClause(pstate,
+ stmt->groupClause,
+ qry->targetList);
- /* fix order clause */
qry->sortClause = transformSortClause(pstate,
stmt->sortClause,
qry->targetList,
qry->uniqueFlag);
- /* fix group by clause */
- qry->groupClause = transformGroupClause(pstate,
- stmt->groupClause,
- qry->targetList);
+ qry->hasSubLinks = pstate->p_hasSubLinks;
+ qry->hasAggs = pstate->p_hasAggs;
+ if (pstate->p_hasAggs || qry->groupClause)
+ parseCheckAggregates(pstate, qry);
+
+ /*
+ * If there is a havingQual but there are no aggregates, then there is
+ * something wrong with the query because HAVING must contain
+ * aggregates in its expressions! Otherwise the query could have been
+ * formulated using the WHERE clause.
+ */
+ if (qry->havingQual && ! qry->hasAggs)
+ elog(ERROR, "SELECT/HAVING requires aggregates to be valid");
+
+ /*
+ * The INSERT INTO ... SELECT ... could have a UNION in child, so
+ * unionClause may be false
+ */
+ qry->unionall = stmt->unionall;
+
+ /*
+ * Just hand through the unionClause and intersectClause. We will
+ * handle it in the function Except_Intersect_Rewrite()
+ */
+ qry->unionClause = stmt->unionClause;
+ qry->intersectClause = stmt->intersectClause;
+
qry->rtable = pstate->p_rtable;
- if (pstate->p_numAgg > 0)
- finalizeAggregates(pstate, qry);
+ if (stmt->forUpdate != NULL)
+ transformForUpdate(qry, stmt->forUpdate);
return (Query *) qry;
}
*
*/
static Query *
-transformUpdateStmt(ParseState *pstate, ReplaceStmt *stmt)
+transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
{
Query *qry = makeNode(Query);
+ List *origTargetList;
+ List *tl;
qry->commandType = CMD_UPDATE;
pstate->p_is_update = true;
* the FROM clause is non-standard SQL syntax. We used to be able to
* do this with REPLACE in POSTQUEL so we keep the feature.
*/
- makeRangeTable(pstate, stmt->relname, stmt->fromClause);
+ makeRangeTable(pstate, stmt->fromClause, NULL);
+ setTargetTable(pstate, stmt->relname);
- /* fix the target list */
qry->targetList = transformTargetList(pstate, stmt->targetList);
- /* fix where clause */
- qry->qual = transformWhereClause(pstate, stmt->whereClause);
+ qry->qual = transformWhereClause(pstate, stmt->whereClause, NULL);
+
+ qry->hasSubLinks = pstate->p_hasSubLinks;
qry->rtable = pstate->p_rtable;
- qry->resultRelation = refnameRangeTablePosn(pstate->p_rtable, stmt->relname);
+ qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
- /* make sure we don't have aggregates in the where clause */
- if (pstate->p_numAgg > 0)
+ qry->hasAggs = pstate->p_hasAggs;
+ if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
+ /*
+ * Now we are done with SELECT-like processing, and can get on with
+ * transforming the target list to match the UPDATE target columns.
+ */
+
+ /* Prepare to assign non-conflicting resnos to resjunk attributes */
+ if (pstate->p_last_resno <= pstate->p_target_relation->rd_rel->relnatts)
+ pstate->p_last_resno = pstate->p_target_relation->rd_rel->relnatts + 1;
+
+ /* Prepare non-junk columns for assignment to target table */
+ origTargetList = stmt->targetList;
+ foreach(tl, qry->targetList)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(tl);
+ Resdom *resnode = tle->resdom;
+ ResTarget *origTarget;
+
+ if (resnode->resjunk)
+ {
+ /* Resjunk nodes need no additional processing, but be sure they
+ * have names and resnos that do not match any target columns;
+ * else rewriter or planner might get confused.
+ */
+ resnode->resname = "?resjunk?";
+ resnode->resno = (AttrNumber) pstate->p_last_resno++;
+ continue;
+ }
+ if (origTargetList == NIL)
+ elog(ERROR, "UPDATE target count mismatch --- internal error");
+ origTarget = (ResTarget *) lfirst(origTargetList);
+ updateTargetListEntry(pstate, tle,
+ origTarget->name, origTarget->indirection);
+ origTargetList = lnext(origTargetList);
+ }
+ if (origTargetList != NIL)
+ elog(ERROR, "UPDATE target count mismatch --- internal error");
+
return (Query *) qry;
}
*
*/
static Query *
-transformCursorStmt(ParseState *pstate, CursorStmt *stmt)
+transformCursorStmt(ParseState *pstate, SelectStmt *stmt)
{
- Query *qry = makeNode(Query);
+ Query *qry;
- /*
- * in the old days, a cursor statement is a 'retrieve into portal'; If
- * you change the following, make sure you also go through the code in
- * various places that tests the kind of operation.
- */
- qry->commandType = CMD_SELECT;
-
- /* set up a range table */
- makeRangeTable(pstate, NULL, stmt->fromClause);
-
- qry->uniqueFlag = stmt->unique;
+ qry = transformSelectStmt(pstate, stmt);
qry->into = stmt->portalname;
+ qry->isTemp = stmt->istemp;
qry->isPortal = TRUE;
qry->isBinary = stmt->binary; /* internal portal */
- /* fix the target list */
- qry->targetList = transformTargetList(pstate, stmt->targetList);
+ return qry;
+}
- /* fix where clause */
- qry->qual = transformWhereClause(pstate, stmt->whereClause);
+/* This function steps through the tree
+ * built up by the select_w_o_sort rule
+ * and builds a list of all SelectStmt Nodes found
+ * The built up list is handed back in **select_list.
+ * If one of the SelectStmt Nodes has the 'unionall' flag
+ * set to true *unionall_present hands back 'true' */
+void
+create_select_list(Node *ptr, List **select_list, bool *unionall_present)
+{
+ if (IsA(ptr, SelectStmt))
+ {
+ *select_list = lappend(*select_list, ptr);
+ if (((SelectStmt *) ptr)->unionall == TRUE)
+ *unionall_present = TRUE;
+ return;
+ }
- /* fix order clause */
- qry->sortClause = transformSortClause(pstate,
- stmt->sortClause,
- qry->targetList,
- qry->uniqueFlag);
- /* fix group by clause */
- qry->groupClause = transformGroupClause(pstate,
- stmt->groupClause,
- qry->targetList);
+ /* Recursively call for all arguments. A NOT expr has no lexpr! */
+ if (((A_Expr *) ptr)->lexpr != NULL)
+ create_select_list(((A_Expr *) ptr)->lexpr, select_list, unionall_present);
+ create_select_list(((A_Expr *) ptr)->rexpr, select_list, unionall_present);
+}
- qry->rtable = pstate->p_rtable;
+/* Changes the A_Expr Nodes to Expr Nodes and exchanges ANDs and ORs.
+ * The reason for the exchange is easy: We implement INTERSECTs and EXCEPTs
+ * by rewriting these queries to semantically equivalent queries that use
+ * IN and NOT IN subselects. To be able to use all three operations
+ * (UNIONs INTERSECTs and EXCEPTs) in one complex query we have to
+ * translate the queries into Disjunctive Normal Form (DNF). Unfortunately
+ * there is no function 'dnfify' but there is a function 'cnfify'
+ * which produces DNF when we exchange ANDs and ORs before calling
+ * 'cnfify' and exchange them back in the result.
+ *
+ * If an EXCEPT or INTERSECT is present *intersect_present
+ * hands back 'true' */
+Node *
+A_Expr_to_Expr(Node *ptr, bool *intersect_present)
+{
+ Node *result = NULL;
- if (pstate->p_numAgg > 0)
- finalizeAggregates(pstate, qry);
+ switch (nodeTag(ptr))
+ {
+ case T_A_Expr:
+ {
+ A_Expr *a = (A_Expr *) ptr;
+
+ switch (a->oper)
+ {
+ case AND:
+ {
+ Expr *expr = makeNode(Expr);
+ Node *lexpr = A_Expr_to_Expr(((A_Expr *) ptr)->lexpr, intersect_present);
+ Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
+
+ *intersect_present = TRUE;
+
+ expr->typeOid = BOOLOID;
+ expr->opType = OR_EXPR;
+ expr->args = makeList(lexpr, rexpr, -1);
+ result = (Node *) expr;
+ break;
+ }
+ case OR:
+ {
+ Expr *expr = makeNode(Expr);
+ Node *lexpr = A_Expr_to_Expr(((A_Expr *) ptr)->lexpr, intersect_present);
+ Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
+
+ expr->typeOid = BOOLOID;
+ expr->opType = AND_EXPR;
+ expr->args = makeList(lexpr, rexpr, -1);
+ result = (Node *) expr;
+ break;
+ }
+ case NOT:
+ {
+ Expr *expr = makeNode(Expr);
+ Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
+
+ expr->typeOid = BOOLOID;
+ expr->opType = NOT_EXPR;
+ expr->args = makeList(rexpr, -1);
+ result = (Node *) expr;
+ break;
+ }
+ }
+ break;
+ }
+ default:
+ result = ptr;
+ }
+ return result;
+}
- return (Query *) qry;
+void
+CheckSelectForUpdate(Query *qry)
+{
+ if (qry->unionClause != NULL)
+ elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT clause");
+ if (qry->uniqueFlag != NULL)
+ elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause");
+ if (qry->groupClause != NULL)
+ elog(ERROR, "SELECT FOR UPDATE is not allowed with GROUP BY clause");
+ if (qry->hasAggs)
+ elog(ERROR, "SELECT FOR UPDATE is not allowed with AGGREGATE");
+}
+
+static void
+transformForUpdate(Query *qry, List *forUpdate)
+{
+ List *rowMark = NULL;
+ RowMark *newrm;
+ List *l;
+ Index i;
+
+ CheckSelectForUpdate(qry);
+
+ if (lfirst(forUpdate) == NULL) /* all tables */
+ {
+ i = 1;
+ foreach(l, qry->rtable)
+ {
+ newrm = makeNode(RowMark);
+ newrm->rti = i++;
+ newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
+ rowMark = lappend(rowMark, newrm);
+ }
+ qry->rowMark = nconc(qry->rowMark, rowMark);
+ return;
+ }
+
+ foreach(l, forUpdate)
+ {
+ List *l2;
+ List *l3;
+
+ i = 1;
+ foreach(l2, qry->rtable)
+ {
+ if (strcmp(((RangeTblEntry *) lfirst(l2))->refname, lfirst(l)) == 0)
+ {
+ foreach(l3, rowMark)
+ {
+ if (((RowMark *) lfirst(l3))->rti == i) /* duplicate */
+ break;
+ }
+ if (l3 == NULL)
+ {
+ newrm = makeNode(RowMark);
+ newrm->rti = i;
+ newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
+ rowMark = lappend(rowMark, newrm);
+ }
+ break;
+ }
+ i++;
+ }
+ if (l2 == NULL)
+ elog(ERROR, "FOR UPDATE: relation %s not found in FROM clause", lfirst(l));
+ }
+
+ qry->rowMark = rowMark;
+ return;
}
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