postgresql/src/backend/parser/analyze.c

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/*-------------------------------------------------------------------------
*
* analyze.c
* transform the parse tree into a query tree
*
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: analyze.c,v 1.156 2000/08/29 04:20:44 momjian Exp $
*
*-------------------------------------------------------------------------
*/
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#include "postgres.h"
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#include "access/heapam.h"
#include "catalog/catname.h"
#include "catalog/pg_index.h"
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#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "parser/analyze.h"
#include "parser/parse.h"
#include "parser/parse_agg.h"
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#include "parser/parse_clause.h"
#include "parser/parse_relation.h"
#include "parser/parse_target.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/relcache.h"
#include "utils/syscache.h"
#ifdef MULTIBYTE
#include "mb/pg_wchar.h"
#endif
void CheckSelectForUpdate(Query *qry); /* no points for style... */
static Query *transformStmt(ParseState *pstate, Node *stmt);
static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
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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);
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static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
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static Query *transformCursorStmt(ParseState *pstate, SelectStmt *stmt);
static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt);
static Query *transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt);
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static void transformForUpdate(Query *qry, List *forUpdate);
static void transformFkeyGetPrimaryKey(FkConstraint *fkconstraint);
static void transformConstraintAttrs(List *constraintList);
static void transformColumnType(ParseState *pstate, ColumnDef *column);
static void transformFkeyCheckAttrs(FkConstraint *fkconstraint);
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/* kluge to return extra info from transformCreateStmt() */
static List *extras_before;
static List *extras_after;
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/*
* parse_analyze -
* analyze a list of parse trees and transform them if necessary.
*
* Returns a list of transformed parse trees. Optimizable statements are
* all transformed to Query while the rest stays the same.
*
*/
List *
parse_analyze(List *pl, ParseState *parentParseState)
{
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List *result = NIL;
ParseState *pstate;
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Query *parsetree;
while (pl != NIL)
{
extras_before = extras_after = NIL;
pstate = make_parsestate(parentParseState);
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parsetree = transformStmt(pstate, lfirst(pl));
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if (pstate->p_target_relation != NULL)
heap_close(pstate->p_target_relation, AccessShareLock);
pstate->p_target_relation = NULL;
pstate->p_target_rangetblentry = NULL;
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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);
}
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result = lappend(result, parsetree);
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while (extras_after != NIL)
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{
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);
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}
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pfree(pstate);
pl = lnext(pl);
}
return result;
}
/*
* transformStmt -
* transform a Parse tree. If it is an optimizable statement, turn it
* into a Query tree.
*/
static Query *
transformStmt(ParseState *pstate, Node *parseTree)
{
Query *result = NULL;
switch (nodeTag(parseTree))
{
/*------------------------
* Non-optimizable statements
*------------------------
*/
case T_CreateStmt:
result = transformCreateStmt(pstate, (CreateStmt *) parseTree);
break;
case T_IndexStmt:
result = transformIndexStmt(pstate, (IndexStmt *) parseTree);
break;
case T_ExtendStmt:
result = transformExtendStmt(pstate, (ExtendStmt *) parseTree);
break;
case T_RuleStmt:
result = transformRuleStmt(pstate, (RuleStmt *) parseTree);
break;
case T_ViewStmt:
{
ViewStmt *n = (ViewStmt *) parseTree;
n->query = (Query *) transformStmt(pstate, (Node *) n->query);
/*
* If a list of column names was given, run through and
* insert these into the actual query tree. - thomas
* 2000-03-08
*/
if (n->aliases != NIL)
{
int i;
List *targetList = n->query->targetList;
if (length(targetList) < length(n->aliases))
elog(ERROR, "CREATE VIEW specifies %d columns"
" but only %d columns are present",
length(targetList), length(n->aliases));
for (i = 0; i < length(n->aliases); i++)
{
Ident *id;
TargetEntry *te;
Resdom *rd;
id = nth(i, n->aliases);
Assert(nodeTag(id) == T_Ident);
te = nth(i, targetList);
Assert(nodeTag(te) == T_TargetEntry);
rd = te->resdom;
Assert(nodeTag(rd) == T_Resdom);
rd->resname = pstrdup(id->name);
}
}
result = makeNode(Query);
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) n;
}
break;
case T_ExplainStmt:
{
ExplainStmt *n = (ExplainStmt *) parseTree;
result = makeNode(Query);
result->commandType = CMD_UTILITY;
n->query = transformStmt(pstate, (Node *) n->query);
result->utilityStmt = (Node *) parseTree;
}
break;
case T_AlterTableStmt:
result = transformAlterTableStmt(pstate, (AlterTableStmt *) parseTree);
break;
case T_SetSessionStmt:
{
List *l;
/* Session is a list of SetVariable nodes
* so just run through the list.
*/
SetSessionStmt *stmt = (SetSessionStmt *) parseTree;
l = stmt->args;
/* First check for duplicate keywords (disallowed by SQL99) */
while (l != NULL)
{
VariableSetStmt *v = (VariableSetStmt *) lfirst(l);
List *ll = lnext(l);
while (ll != NULL)
{
VariableSetStmt *vv = (VariableSetStmt *) lfirst(ll);
if (strcmp(v->name, vv->name) == 0)
elog(ERROR, "SET SESSION CHARACTERISTICS duplicated entry not allowed");
ll = lnext(ll);
}
l = lnext(l);
}
l = stmt->args;
result = transformStmt(pstate, lfirst(l));
l = lnext(l);
if (l != NULL)
extras_after = lappend(extras_after, lfirst(l));
}
break;
/*------------------------
* Optimizable statements
*------------------------
*/
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case T_InsertStmt:
result = transformInsertStmt(pstate, (InsertStmt *) parseTree);
break;
case T_DeleteStmt:
result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
break;
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case T_UpdateStmt:
result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
break;
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case T_SelectStmt:
if (!((SelectStmt *) parseTree)->portalname)
{
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result = transformSelectStmt(pstate, (SelectStmt *) parseTree);
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result->limitOffset = ((SelectStmt *) parseTree)->limitOffset;
result->limitCount = ((SelectStmt *) parseTree)->limitCount;
}
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else
result = transformCursorStmt(pstate, (SelectStmt *) parseTree);
break;
default:
/*
* other statments don't require any transformation-- just
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* return the original parsetree, yea!
*/
result = makeNode(Query);
result->commandType = CMD_UTILITY;
result->utilityStmt = (Node *) parseTree;
break;
}
return result;
}
/*
* transformDeleteStmt -
* transforms a Delete Statement
*/
static Query *
transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt)
{
Query *qry = makeNode(Query);
qry->commandType = CMD_DELETE;
/* set up a range table */
makeRangeTable(pstate, NULL);
setTargetTable(pstate, stmt->relname, stmt->inh);
qry->distinctClause = NIL;
/* fix where clause */
qry->qual = transformWhereClause(pstate, stmt->whereClause);
qry->rtable = pstate->p_rtable;
qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
qry->hasSubLinks = pstate->p_hasSubLinks;
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qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
return (Query *) qry;
}
/*
* transformInsertStmt -
* transform an Insert Statement
*/
static Query *
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transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
{
Query *qry = makeNode(Query);
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List *icolumns;
List *attrnos;
List *attnos;
int numuseratts;
List *tl;
TupleDesc rd_att;
qry->commandType = CMD_INSERT;
pstate->p_is_insert = true;
/*----------
* 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...)
*----------
*/
/* set up a range table --- note INSERT target is not in it yet */
makeRangeTable(pstate, stmt->fromClause);
qry->targetList = transformTargetList(pstate, stmt->targetList);
qry->qual = transformWhereClause(pstate, stmt->whereClause);
/*
* 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);
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qry->groupClause = transformGroupClause(pstate,
stmt->groupClause,
qry->targetList);
/* An InsertStmt has no sortClause */
qry->sortClause = NIL;
qry->distinctClause = transformDistinctClause(pstate,
stmt->distinctClause,
qry->targetList,
&qry->sortClause);
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qry->hasSubLinks = pstate->p_hasSubLinks;
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qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
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parseCheckAggregates(pstate, qry);
/*
* The INSERT INTO ... SELECT ... could have a UNION in child, so
* unionClause may be false
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*/
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;
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/*
* 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, FALSE);
/* 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 = checkInsertTargets(pstate, stmt->cols, &attrnos);
/* Prepare non-junk columns for assignment to target table */
numuseratts = 0;
attnos = attrnos;
foreach(tl, qry->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(tl);
Resdom *resnode = tle->resdom;
Ident *id;
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 (icolumns == NIL || attnos == NIL)
elog(ERROR, "INSERT has more expressions than target columns");
id = (Ident *) lfirst(icolumns);
updateTargetListEntry(pstate, tle, id->name, lfirsti(attnos),
id->indirection);
numuseratts++;
icolumns = lnext(icolumns);
attnos = lnext(attnos);
}
/*
* It is possible that the targetlist has fewer entries than were in
* the columns list. We do not consider this an error (perhaps we
* should, if the columns list was explictly given?). We must
* truncate the attrnos list to only include the attrs actually
* provided, else we will fail to apply defaults for them below.
*/
if (icolumns != NIL)
attrnos = ltruncate(numuseratts, attrnos);
/*
* 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)
{
AttrNumber attrno = defval[ndef].adnum;
Form_pg_attribute thisatt = att[attrno - 1];
TargetEntry *te;
if (intMember((int) attrno, attrnos))
continue; /* there was a user-specified value */
/*
* No user-supplied value, so add a targetentry with DEFAULT
* expr and correct data for the target column.
*/
te = makeTargetEntry(
makeResdom(attrno,
thisatt->atttypid,
thisatt->atttypmod,
pstrdup(NameStr(thisatt->attname)),
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, attrno,
NIL);
}
}
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if (stmt->forUpdate != NULL)
transformForUpdate(qry, stmt->forUpdate);
/* in case of subselects in default clauses... */
qry->hasSubLinks = pstate->p_hasSubLinks;
return (Query *) qry;
}
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/*
* 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--;
}
#ifdef MULTIBYTE
if (name1)
name1chars = pg_mbcliplen(name1, name1chars, name1chars);
if (name2)
name2chars = pg_mbcliplen(name2, name2chars, name2chars);
#endif
/* 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';
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return name;
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}
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static char *
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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 (strcmp(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);
}
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return iname;
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}
/*
* 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 *
transformCreateStmt(ParseState *pstate, CreateStmt *stmt)
{
Query *q;
List *elements;
Node *element;
List *columns;
List *dlist;
ColumnDef *column;
List *constraints,
*clist;
Constraint *constraint;
List *fkconstraints, /* List of FOREIGN KEY constraints to */
*fkclist; /* add finally */
FkConstraint *fkconstraint;
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;
bool saw_nullable;
q = makeNode(Query);
q->commandType = CMD_UTILITY;
fkconstraints = NIL;
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);
transformColumnType(pstate, column);
/* Special case SERIAL type? */
if (column->is_sequence)
{
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char *sname;
char *qstring;
A_Const *snamenode;
FuncCall *funccallnode;
CreateSeqStmt *sequence;
/*
* Create appropriate constraints for SERIAL. We do
* this in full, rather than shortcutting, so that we
* will detect any conflicting constraints the user
* wrote (like a different DEFAULT).
*/
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);
funccallnode->agg_star = false;
funccallnode->agg_distinct = false;
constraint = makeNode(Constraint);
constraint->contype = CONSTR_DEFAULT;
constraint->name = sname;
constraint->raw_expr = (Node *) funccallnode;
constraint->cooked_expr = NULL;
constraint->keys = NIL;
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);
constraint = makeNode(Constraint);
constraint->contype = CONSTR_NOTNULL;
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);
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blist = lcons(sequence, NIL);
}
/* Process column constraints, if any... */
transformConstraintAttrs(column->constraints);
saw_nullable = false;
foreach(clist, column->constraints)
{
constraint = lfirst(clist);
/* ----------
* If this column constraint is a FOREIGN KEY
* constraint, then we fill in the current attributes
* name and throw it into the list of FK constraints
* to be processed later.
* ----------
*/
if (IsA(constraint, FkConstraint))
{
Ident *id = makeNode(Ident);
id->name = column->colname;
id->indirection = NIL;
id->isRel = false;
fkconstraint = (FkConstraint *) constraint;
fkconstraint->fk_attrs = lappend(NIL, id);
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fkconstraints = lappend(fkconstraints, constraint);
continue;
}
switch (constraint->contype)
{
case CONSTR_NULL:
if (saw_nullable && column->is_not_null)
elog(ERROR, "CREATE TABLE/(NOT) NULL conflicting declaration"
" for '%s.%s'", stmt->relname, column->colname);
column->is_not_null = FALSE;
saw_nullable = true;
break;
case CONSTR_NOTNULL:
if (saw_nullable && !column->is_not_null)
elog(ERROR, "CREATE TABLE/(NOT) NULL conflicting declaration"
" for '%s.%s'", stmt->relname, column->colname);
column->is_not_null = TRUE;
saw_nullable = 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)
{
key = makeNode(Ident);
key->name = pstrdup(column->colname);
constraint->keys = lcons(key, NIL);
}
dlist = lappend(dlist, constraint);
break;
case CONSTR_UNIQUE:
if (constraint->name == NULL)
constraint->name = makeObjectName(stmt->relname, column->colname, "key");
if (constraint->keys == NIL)
{
key = makeNode(Ident);
key->name = pstrdup(column->colname);
constraint->keys = lcons(key, NIL);
}
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;
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
/* transformConstraintAttrs took care of these */
break;
default:
elog(ERROR, "parser: unrecognized constraint (internal error)");
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_NULL:
case CONSTR_NOTNULL:
case CONSTR_DEFAULT:
case CONSTR_ATTR_DEFERRABLE:
case CONSTR_ATTR_NOT_DEFERRABLE:
case CONSTR_ATTR_DEFERRED:
case CONSTR_ATTR_IMMEDIATE:
elog(ERROR, "parser: illegal context for constraint (internal error)");
break;
default:
elog(ERROR, "parser: unrecognized constraint (internal error)");
break;
}
break;
case T_FkConstraint:
/* ----------
* Table level FOREIGN KEY constraints are already complete.
* Just remember for later.
* ----------
*/
fkconstraints = lappend(fkconstraints, element);
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)
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|| (constraint->contype == CONSTR_UNIQUE));
index = makeNode(IndexStmt);
index->unique = TRUE;
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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;
foreach(keys, constraint->keys)
{
key = (Ident *) lfirst(keys);
Assert(IsA(key, Ident));
column = NULL;
foreach(columns, stmt->tableElts)
{
column = lfirst(columns);
Assert(IsA(column, ColumnDef));
if (strcmp(column->colname, key->name) == 0)
break;
}
if (columns == NIL) /* fell off end of list? */
elog(ERROR, "CREATE TABLE: column '%s' named 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;
index->indexParams = lappend(index->indexParams, iparam);
if (index->idxname == NULL)
index->idxname = CreateIndexName(stmt->relname, iparam->name, "key", ilist);
}
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;
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/* 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'",
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(index->primary ? "PRIMARY KEY" : "UNIQUE"),
index->idxname, stmt->relname);
dlist = lnext(dlist);
}
q->utilityStmt = (Node *) stmt;
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extras_before = blist;
extras_after = ilist;
/*
* Now process the FOREIGN KEY constraints and add appropriate queries
* to the extras_after statements list.
*
*/
if (fkconstraints != NIL)
{
CreateTrigStmt *fk_trigger;
List *fk_attr;
List *pk_attr;
Ident *id;
elog(NOTICE, "CREATE TABLE will create implicit trigger(s) for FOREIGN KEY check(s)");
foreach(fkclist, fkconstraints)
{
fkconstraint = (FkConstraint *) lfirst(fkclist);
/*
* If the constraint has no name, set it to <unnamed>
*
*/
if (fkconstraint->constr_name == NULL)
fkconstraint->constr_name = "<unnamed>";
/*
* Check to see if the attributes mentioned by the constraint
* actually exist on this table.
*/
if (fkconstraint->fk_attrs!=NIL) {
int found=0;
List *cols;
List *fkattrs;
Ident *fkattr;
ColumnDef *col;
foreach(fkattrs, fkconstraint->fk_attrs) {
found=0;
fkattr=lfirst(fkattrs);
foreach(cols, columns) {
col=lfirst(cols);
if (strcmp(col->colname, fkattr->name)==0) {
found=1;
break;
}
}
if (!found)
break;
}
if (!found)
elog(ERROR, "columns referenced in foreign key constraint not found.");
}
/*
* If the attribute list for the referenced table was omitted,
* lookup for the definition of the primary key. If the
* referenced table is this table, use the definition we found
* above, rather than looking to the system tables.
*
*/
if (fkconstraint->fk_attrs != NIL && fkconstraint->pk_attrs == NIL)
{
if (strcmp(fkconstraint->pktable_name, stmt->relname) != 0)
transformFkeyGetPrimaryKey(fkconstraint);
else if (pkey != NULL)
{
List *pkey_attr = pkey->indexParams;
List *attr;
IndexElem *ielem;
Ident *pkattr;
foreach(attr, pkey_attr)
{
ielem = lfirst(attr);
pkattr = (Ident *) makeNode(Ident);
pkattr->name = pstrdup(ielem->name);
pkattr->indirection = NIL;
pkattr->isRel = false;
fkconstraint->pk_attrs = lappend(fkconstraint->pk_attrs, pkattr);
}
}
else
{
elog(ERROR, "PRIMARY KEY for referenced table \"%s\" not found",
fkconstraint->pktable_name);
}
}
else {
if (strcmp(fkconstraint->pktable_name, stmt->relname)!=0)
transformFkeyCheckAttrs(fkconstraint);
else {
/* Get a unique/pk constraint from above */
List *index;
int found=0;
foreach(index, ilist)
{
IndexStmt *ind=lfirst(index);
IndexElem *indparm;
List *indparms;
List *pkattrs;
Ident *pkattr;
if (ind->unique) {
foreach(pkattrs, fkconstraint->pk_attrs) {
found=0;
pkattr=lfirst(pkattrs);
foreach(indparms, ind->indexParams) {
indparm=lfirst(indparms);
if (strcmp(indparm->name, pkattr->name)==0) {
found=1;
break;
}
}
if (!found)
break;
}
}
if (found)
break;
}
if (!found)
elog(ERROR, "UNIQUE constraint matching given keys for referenced table \"%s\" not found",
fkconstraint->pktable_name);
}
}
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the CHECK
* action.
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = stmt->relname;
fk_trigger->funcname = "RI_FKey_check_ins";
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'i';
fk_trigger->actions[1] = 'u';
fk_trigger->actions[2] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = fkconstraint->pktable_name;
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
if (length(fk_attr) != length(pk_attr))
{
elog(NOTICE, "Illegal FOREIGN KEY definition REFERENCES \"%s\"",
fkconstraint->pktable_name);
elog(ERROR, "number of key attributes in referenced table must be equal to foreign key");
}
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the ON
* DELETE action fired on the PK table !!!
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = fkconstraint->pktable_name;
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'd';
fk_trigger->actions[1] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = stmt->relname;
switch ((fkconstraint->actions & FKCONSTR_ON_DELETE_MASK)
>> FKCONSTR_ON_DELETE_SHIFT)
{
case FKCONSTR_ON_KEY_NOACTION:
fk_trigger->funcname = "RI_FKey_noaction_del";
break;
case FKCONSTR_ON_KEY_RESTRICT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = "RI_FKey_restrict_del";
break;
case FKCONSTR_ON_KEY_CASCADE:
fk_trigger->funcname = "RI_FKey_cascade_del";
break;
case FKCONSTR_ON_KEY_SETNULL:
fk_trigger->funcname = "RI_FKey_setnull_del";
break;
case FKCONSTR_ON_KEY_SETDEFAULT:
fk_trigger->funcname = "RI_FKey_setdefault_del";
break;
default:
elog(ERROR, "Only one ON DELETE action can be specified for FOREIGN KEY constraint");
break;
}
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the ON
* UPDATE action fired on the PK table !!!
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = fkconstraint->pktable_name;
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'u';
fk_trigger->actions[1] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = stmt->relname;
switch ((fkconstraint->actions & FKCONSTR_ON_UPDATE_MASK)
>> FKCONSTR_ON_UPDATE_SHIFT)
{
case FKCONSTR_ON_KEY_NOACTION:
fk_trigger->funcname = "RI_FKey_noaction_upd";
break;
case FKCONSTR_ON_KEY_RESTRICT:
fk_trigger->deferrable = false;
fk_trigger->initdeferred = false;
fk_trigger->funcname = "RI_FKey_restrict_upd";
break;
case FKCONSTR_ON_KEY_CASCADE:
fk_trigger->funcname = "RI_FKey_cascade_upd";
break;
case FKCONSTR_ON_KEY_SETNULL:
fk_trigger->funcname = "RI_FKey_setnull_upd";
break;
case FKCONSTR_ON_KEY_SETDEFAULT:
fk_trigger->funcname = "RI_FKey_setdefault_upd";
break;
default:
elog(ERROR, "Only one ON UPDATE action can be specified for FOREIGN KEY constraint");
break;
}
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
}
}
return q;
1999-05-25 18:15:34 +02:00
} /* transformCreateStmt() */
/*
* transformIndexStmt -
* transforms the qualification of the index statement
*/
static Query *
transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
{
1998-02-06 17:46:29 +01:00
Query *qry;
1998-02-06 17:46:29 +01:00
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/* take care of the where clause */
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
1998-02-06 17:46:29 +01:00
qry->hasSubLinks = pstate->p_hasSubLinks;
stmt->rangetable = pstate->p_rtable;
1998-02-06 17:46:29 +01:00
qry->utilityStmt = (Node *) stmt;
1998-02-06 17:46:29 +01:00
return qry;
}
/*
* transformExtendStmt -
* transform the qualifications of the Extend Index Statement
*
*/
static Query *
transformExtendStmt(ParseState *pstate, ExtendStmt *stmt)
{
1998-02-06 17:46:29 +01:00
Query *qry;
1998-02-06 17:46:29 +01:00
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/* take care of the where clause */
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
1998-02-06 17:46:29 +01:00
qry->hasSubLinks = pstate->p_hasSubLinks;
stmt->rangetable = pstate->p_rtable;
1998-02-06 17:46:29 +01:00
qry->utilityStmt = (Node *) stmt;
return qry;
}
/*
* transformRuleStmt -
* transform a Create Rule Statement. The actions is a list of parse
* trees which is transformed into a list of query trees.
*/
static Query *
transformRuleStmt(ParseState *pstate, RuleStmt *stmt)
{
1998-02-06 17:46:29 +01:00
Query *qry;
Query *action;
List *actions;
1998-02-06 17:46:29 +01:00
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,
makeAttr("*OLD*", NULL),
FALSE, FALSE, FALSE);
addRangeTableEntry(pstate, stmt->object->relname,
makeAttr("*NEW*", NULL),
FALSE, FALSE, FALSE);
nothing_qry->rtable = pstate->p_rtable;
stmt->actions = lappend(NIL, nothing_qry);
}
actions = stmt->actions;
/*
* transform each statment, like parse_analyze()
*/
while (actions != NIL)
{
/*
* NOTE: 'OLD' must always have a varno equal to 1 and 'NEW'
* equal to 2.
*/
addRangeTableEntry(pstate, stmt->object->relname,
makeAttr("*OLD*", NULL),
FALSE, FALSE, FALSE);
addRangeTableEntry(pstate, stmt->object->relname,
makeAttr("*NEW*", NULL),
FALSE, FALSE, FALSE);
pstate->p_last_resno = 1;
pstate->p_is_rule = true; /* for expand all */
pstate->p_hasAggs = false;
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);
1998-02-06 17:46:29 +01:00
qry->hasSubLinks = pstate->p_hasSubLinks;
1998-02-06 17:46:29 +01:00
qry->utilityStmt = (Node *) stmt;
return qry;
}
/*
* transformSelectStmt -
* transforms a Select Statement
*
*/
static Query *
1998-01-09 21:06:08 +01:00
transformSelectStmt(ParseState *pstate, SelectStmt *stmt)
{
Query *qry = makeNode(Query);
qry->commandType = CMD_SELECT;
/* set up a range table */
makeRangeTable(pstate, stmt->fromClause);
qry->into = stmt->into;
qry->isTemp = stmt->istemp;
qry->isPortal = FALSE;
qry->targetList = transformTargetList(pstate, stmt->targetList);
qry->qual = transformWhereClause(pstate, stmt->whereClause);
/*
* 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);
qry->groupClause = transformGroupClause(pstate,
stmt->groupClause,
qry->targetList);
qry->sortClause = transformSortClause(pstate,
stmt->sortClause,
qry->targetList);
qry->distinctClause = transformDistinctClause(pstate,
stmt->distinctClause,
qry->targetList,
&qry->sortClause);
qry->hasSubLinks = pstate->p_hasSubLinks;
1998-01-20 06:05:08 +01:00
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
1998-01-20 06:05:08 +01:00
parseCheckAggregates(pstate, qry);
/*
* The INSERT INTO ... SELECT ... could have a UNION in child, so
* unionClause may be false
*/
qry->unionall = stmt->unionall;
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
1999-05-25 18:15:34 +02:00
/*
* 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;
1999-01-21 17:08:55 +01:00
if (stmt->forUpdate != NULL)
transformForUpdate(qry, stmt->forUpdate);
return (Query *) qry;
}
/*
* transformUpdateStmt -
* transforms an update statement
*
*/
static Query *
1998-01-09 21:06:08 +01:00
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->fromClause);
setTargetTable(pstate, stmt->relname, stmt->inh);
qry->targetList = transformTargetList(pstate, stmt->targetList);
qry->qual = transformWhereClause(pstate, stmt->whereClause);
1998-02-06 17:46:29 +01:00
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->rtable = pstate->p_rtable;
qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
1998-01-10 05:30:11 +01:00
1998-01-20 06:05:08 +01:00
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,
attnameAttNum(pstate->p_target_relation,
origTarget->name),
origTarget->indirection);
origTargetList = lnext(origTargetList);
}
if (origTargetList != NIL)
elog(ERROR, "UPDATE target count mismatch --- internal error");
return (Query *) qry;
}
/*
* transformCursorStmt -
* transform a Create Cursor Statement
*
*/
static Query *
1998-01-10 05:30:11 +01:00
transformCursorStmt(ParseState *pstate, SelectStmt *stmt)
{
1998-01-10 05:30:11 +01:00
Query *qry;
1998-01-10 05:30:11 +01:00
qry = transformSelectStmt(pstate, stmt);
qry->into = stmt->portalname;
qry->isTemp = stmt->istemp;
qry->isPortal = TRUE;
qry->isBinary = stmt->binary; /* internal portal */
1998-01-10 05:30:11 +01:00
return qry;
}
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
/*
* tranformAlterTableStmt -
* transform an Alter Table Statement
*
*/
static Query *
transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt)
{
Query *qry;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/*
* The only subtypes that currently have special handling are 'A'dd
* column and Add 'C'onstraint. In addition, right now only Foreign
* Key 'C'onstraints have a special transformation.
*
*/
switch (stmt->subtype)
{
case 'A':
transformColumnType(pstate, (ColumnDef *) stmt->def);
break;
case 'C':
if (stmt->def && nodeTag(stmt->def) == T_FkConstraint)
{
CreateTrigStmt *fk_trigger;
List *fk_attr;
List *pk_attr;
Ident *id;
FkConstraint *fkconstraint;
extras_after = NIL;
elog(NOTICE, "ALTER TABLE ... ADD CONSTRAINT will create implicit trigger(s) for FOREIGN KEY check(s)");
fkconstraint = (FkConstraint *) stmt->def;
/*
* If the constraint has no name, set it to <unnamed>
*
*/
if (fkconstraint->constr_name == NULL)
fkconstraint->constr_name = "<unnamed>";
/*
* If the attribute list for the referenced table was
* omitted, lookup for the definition of the primary key
*
*/
if (fkconstraint->fk_attrs != NIL && fkconstraint->pk_attrs == NIL)
transformFkeyGetPrimaryKey(fkconstraint);
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the
* CHECK action.
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = stmt->relname;
fk_trigger->funcname = "RI_FKey_check_ins";
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'i';
fk_trigger->actions[1] = 'u';
fk_trigger->actions[2] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = fkconstraint->pktable_name;
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
if (length(fk_attr) != length(pk_attr))
{
elog(NOTICE, "Illegal FOREIGN KEY definition REFERENCES \"%s\"",
fkconstraint->pktable_name);
elog(ERROR, "number of key attributes in referenced table must be equal to foreign key");
}
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the ON
* DELETE action fired on the PK table !!!
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = fkconstraint->pktable_name;
switch ((fkconstraint->actions & FKCONSTR_ON_DELETE_MASK)
>> FKCONSTR_ON_DELETE_SHIFT)
{
case FKCONSTR_ON_KEY_NOACTION:
fk_trigger->funcname = "RI_FKey_noaction_del";
break;
case FKCONSTR_ON_KEY_RESTRICT:
fk_trigger->funcname = "RI_FKey_restrict_del";
break;
case FKCONSTR_ON_KEY_CASCADE:
fk_trigger->funcname = "RI_FKey_cascade_del";
break;
case FKCONSTR_ON_KEY_SETNULL:
fk_trigger->funcname = "RI_FKey_setnull_del";
break;
case FKCONSTR_ON_KEY_SETDEFAULT:
fk_trigger->funcname = "RI_FKey_setdefault_del";
break;
default:
elog(ERROR, "Only one ON DELETE action can be specified for FOREIGN KEY constraint");
break;
}
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'd';
fk_trigger->actions[1] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = stmt->relname;
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
/*
* Build a CREATE CONSTRAINT TRIGGER statement for the ON
* UPDATE action fired on the PK table !!!
*
*/
fk_trigger = (CreateTrigStmt *) makeNode(CreateTrigStmt);
fk_trigger->trigname = fkconstraint->constr_name;
fk_trigger->relname = fkconstraint->pktable_name;
switch ((fkconstraint->actions & FKCONSTR_ON_UPDATE_MASK)
>> FKCONSTR_ON_UPDATE_SHIFT)
{
case FKCONSTR_ON_KEY_NOACTION:
fk_trigger->funcname = "RI_FKey_noaction_upd";
break;
case FKCONSTR_ON_KEY_RESTRICT:
fk_trigger->funcname = "RI_FKey_restrict_upd";
break;
case FKCONSTR_ON_KEY_CASCADE:
fk_trigger->funcname = "RI_FKey_cascade_upd";
break;
case FKCONSTR_ON_KEY_SETNULL:
fk_trigger->funcname = "RI_FKey_setnull_upd";
break;
case FKCONSTR_ON_KEY_SETDEFAULT:
fk_trigger->funcname = "RI_FKey_setdefault_upd";
break;
default:
elog(ERROR, "Only one ON UPDATE action can be specified for FOREIGN KEY constraint");
break;
}
fk_trigger->before = false;
fk_trigger->row = true;
fk_trigger->actions[0] = 'u';
fk_trigger->actions[1] = '\0';
fk_trigger->lang = NULL;
fk_trigger->text = NULL;
fk_trigger->attr = NIL;
fk_trigger->when = NULL;
fk_trigger->isconstraint = true;
fk_trigger->deferrable = fkconstraint->deferrable;
fk_trigger->initdeferred = fkconstraint->initdeferred;
fk_trigger->constrrelname = stmt->relname;
fk_trigger->args = NIL;
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->constr_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(stmt->relname));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->pktable_name));
fk_trigger->args = lappend(fk_trigger->args,
makeString(fkconstraint->match_type));
fk_attr = fkconstraint->fk_attrs;
pk_attr = fkconstraint->pk_attrs;
while (fk_attr != NIL)
{
id = (Ident *) lfirst(fk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args,
makeString(id->name));
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
}
break;
default:
break;
}
qry->utilityStmt = (Node *) stmt;
return qry;
}
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
/* 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' */
1999-05-25 18:15:34 +02:00
void
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
create_select_list(Node *ptr, List **select_list, bool *unionall_present)
{
1999-05-25 18:15:34 +02:00
if (IsA(ptr, SelectStmt))
{
*select_list = lappend(*select_list, ptr);
if (((SelectStmt *) ptr)->unionall == TRUE)
*unionall_present = TRUE;
return;
}
/* 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);
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
}
/* Changes the A_Expr Nodes to Expr Nodes and exchanges ANDs and ORs.
1999-05-25 18:15:34 +02:00
* The reason for the exchange is easy: We implement INTERSECTs and EXCEPTs
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
* by rewriting these queries to semantically equivalent queries that use
1999-05-25 18:15:34 +02:00
* IN and NOT IN subselects. To be able to use all three operations
* (UNIONs INTERSECTs and EXCEPTs) in one complex query we have to
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
* 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
1999-05-25 18:15:34 +02:00
* hands back 'true' */
Node *
A_Expr_to_Expr(Node *ptr, bool *intersect_present)
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
{
1999-05-25 18:15:34 +02:00
Node *result = NULL;
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;
1999-05-25 18:15:34 +02:00
}
return result;
Hi! INTERSECT and EXCEPT is available for postgresql-v6.4! The patch against v6.4 is included at the end of the current text (in uuencoded form!) I also included the text of my Master's Thesis. (a postscript version). I hope that you find something of it useful and would be happy if parts of it find their way into the PostgreSQL documentation project (If so, tell me, then I send the sources of the document!) The contents of the document are: -) The first chapter might be of less interest as it gives only an overview on SQL. -) The second chapter gives a description on much of PostgreSQL's features (like user defined types etc. and how to use these features) -) The third chapter starts with an overview of PostgreSQL's internal structure with focus on the stages a query has to pass (i.e. parser, planner/optimizer, executor). Then a detailed description of the implementation of the Having clause and the Intersect/Except logic is given. Originally I worked on v6.3.2 but never found time enough to prepare and post a patch. Now I applied the changes to v6.4 to get Intersect and Except working with the new version. Chapter 3 of my documentation deals with the changes against v6.3.2, so keep that in mind when comparing the parts of the code printed there with the patched sources of v6.4. Here are some remarks on the patch. There are some things that have still to be done but at the moment I don't have time to do them myself. (I'm doing my military service at the moment) Sorry for that :-( -) I used a rewrite technique for the implementation of the Except/Intersect logic which rewrites the query to a semantically equivalent query before it is handed to the rewrite system (for views, rules etc.), planner, executor etc. -) In v6.3.2 the types of the attributes of two select statements connected by the UNION keyword had to match 100%. In v6.4 the types only need to be familiar (i.e. int and float can be mixed). Since this feature did not exist when I worked on Intersect/Except it does not work correctly for Except/Intersect queries WHEN USED IN COMBINATION WITH UNIONS! (i.e. sometimes the wrong type is used for the resulting table. This is because until now the types of the attributes of the first select statement have been used for the resulting table. When Intersects and/or Excepts are used in combination with Unions it might happen, that the first select statement of the original query appears at another position in the query which will be executed. The reason for this is the technique used for the implementation of Except/Intersect which does a query rewrite!) NOTE: It is NOT broken for pure UNION queries and pure INTERSECT/EXCEPT queries!!! -) I had to add the field intersect_clause to some data structures but did not find time to implement printfuncs for the new field. This does NOT break the debug modes but when an Except/Intersect is used the query debug output will be the already rewritten query. -) Massive changes to the grammar rules for SELECT and INSERT statements have been necessary (see comments in gram.y and documentation for deatails) in order to be able to use mixed queries like (SELECT ... UNION (SELECT ... EXCEPT SELECT)) INTERSECT SELECT...; -) When using UNION/EXCEPT/INTERSECT you will get: NOTICE: equal: "Don't know if nodes of type xxx are equal". I did not have time to add comparsion support for all the needed nodes, but the default behaviour of the function equal met my requirements. I did not dare to supress this message! That's the reason why the regression test for union will fail: These messages are also included in the union.out file! -) Somebody of you changed the union_planner() function for v6.4 (I copied the targetlist to new_tlist and that was removed and replaced by a cleanup of the original targetlist). These chnages violated some having queries executed against views so I changed it back again. I did not have time to examine the differences between the two versions but now it works :-) If you want to find out, try the file queries/view_having.sql on both versions and compare the results . Two queries won't produce a correct result with your version. regards Stefan
1999-01-18 01:10:17 +01:00
}
1999-01-21 17:08:55 +01:00
1999-01-25 13:01:19 +01:00
void
CheckSelectForUpdate(Query *qry)
{
if (qry->unionClause != NULL)
elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT clause");
if (qry->distinctClause != NIL)
1999-01-25 13:01:19 +01:00
elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause");
if (qry->groupClause != NIL)
1999-01-25 13:01:19 +01:00
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");
}
1999-01-21 17:08:55 +01:00
static void
transformForUpdate(Query *qry, List *forUpdate)
{
List *rowMark = NULL;
1999-05-25 18:15:34 +02:00
RowMark *newrm;
1999-01-21 17:08:55 +01:00
List *l;
Index i;
1999-01-25 13:01:19 +01:00
CheckSelectForUpdate(qry);
1999-01-21 17:08:55 +01:00
if (lfirst(forUpdate) == NULL) /* all tables */
{
i = 1;
1999-05-25 18:15:34 +02:00
foreach(l, qry->rtable)
1999-01-21 17:08:55 +01:00
{
newrm = makeNode(RowMark);
newrm->rti = i++;
1999-05-25 18:15:34 +02:00
newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
1999-01-21 17:08:55 +01:00
rowMark = lappend(rowMark, newrm);
}
qry->rowMark = nconc(qry->rowMark, rowMark);
return;
}
1999-05-25 18:15:34 +02:00
foreach(l, forUpdate)
1999-01-21 17:08:55 +01:00
{
2000-01-16 09:21:59 +01:00
char *relname = lfirst(l);
1999-05-25 18:15:34 +02:00
List *l2;
1999-01-21 17:08:55 +01:00
i = 1;
1999-05-25 18:15:34 +02:00
foreach(l2, qry->rtable)
1999-01-21 17:08:55 +01:00
{
if (strcmp(((RangeTblEntry *) lfirst(l2))->eref->relname, relname) == 0)
1999-01-21 17:08:55 +01:00
{
2000-01-16 09:21:59 +01:00
List *l3;
1999-05-25 18:15:34 +02:00
foreach(l3, rowMark)
1999-01-21 17:08:55 +01:00
{
1999-05-25 18:15:34 +02:00
if (((RowMark *) lfirst(l3))->rti == i) /* duplicate */
1999-01-21 17:08:55 +01:00
break;
}
if (l3 == NULL)
{
newrm = makeNode(RowMark);
newrm->rti = i;
1999-05-25 18:15:34 +02:00
newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
1999-01-21 17:08:55 +01:00
rowMark = lappend(rowMark, newrm);
}
break;
}
i++;
}
if (l2 == NULL)
elog(ERROR, "FOR UPDATE: relation '%s' not found in FROM clause",
2000-01-16 09:21:59 +01:00
relname);
1999-01-21 17:08:55 +01:00
}
qry->rowMark = rowMark;
}
/*
* transformFkeyCheckAttrs -
*
* Try to make sure that the attributes of a referenced table
* belong to a unique (or primary key) constraint.
*
*/
static void
transformFkeyCheckAttrs(FkConstraint *fkconstraint)
{
Relation pkrel;
Form_pg_attribute *pkrel_attrs;
List *indexoidlist,
*indexoidscan;
Form_pg_index indexStruct = NULL;
int i;
int found=0;
/* ----------
* Open the referenced table and get the attributes list
* ----------
*/
pkrel = heap_openr(fkconstraint->pktable_name, AccessShareLock);
if (pkrel == NULL)
elog(ERROR, "referenced table \"%s\" not found",
fkconstraint->pktable_name);
pkrel_attrs = pkrel->rd_att->attrs;
/* ----------
* Get the list of index OIDs for the table from the relcache,
* and look up each one in the pg_index syscache for each unique
* one, and then compare the attributes we were given to those
* defined.
* ----------
*/
indexoidlist = RelationGetIndexList(pkrel);
foreach(indexoidscan, indexoidlist)
{
Oid indexoid = lfirsti(indexoidscan);
HeapTuple indexTuple;
List *attrl;
indexTuple = SearchSysCacheTuple(INDEXRELID,
ObjectIdGetDatum(indexoid),
0, 0, 0);
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "transformFkeyGetPrimaryKey: index %u not found",
indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
if (indexStruct->indisunique) {
/* go through the fkconstraint->pk_attrs list */
foreach(attrl, fkconstraint->pk_attrs) {
Ident *attr=lfirst(attrl);
found=0;
for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
{
int pkattno = indexStruct->indkey[i];
if (pkattno>0) {
char *name = NameStr(pkrel_attrs[pkattno - 1]->attname);
if (strcmp(name, attr->name)==0) {
found=1;
break;
}
}
}
if (!found)
break;
}
}
if (found)
break;
indexStruct = NULL;
}
if (!found)
elog(ERROR, "UNIQUE constraint matching given keys for referenced table \"%s\" not found",
fkconstraint->pktable_name);
freeList(indexoidlist);
heap_close(pkrel, AccessShareLock);
}
/*
* transformFkeyGetPrimaryKey -
*
* Try to find the primary key attributes of a referenced table if
* the column list in the REFERENCES specification was omitted.
*
*/
static void
transformFkeyGetPrimaryKey(FkConstraint *fkconstraint)
{
Relation pkrel;
Form_pg_attribute *pkrel_attrs;
List *indexoidlist,
*indexoidscan;
Form_pg_index indexStruct = NULL;
int i;
/* ----------
* Open the referenced table and get the attributes list
* ----------
*/
pkrel = heap_openr(fkconstraint->pktable_name, AccessShareLock);
if (pkrel == NULL)
elog(ERROR, "referenced table \"%s\" not found",
fkconstraint->pktable_name);
pkrel_attrs = pkrel->rd_att->attrs;
/* ----------
* Get the list of index OIDs for the table from the relcache,
* and look up each one in the pg_index syscache until we find one
* marked primary key (hopefully there isn't more than one such).
* ----------
*/
indexoidlist = RelationGetIndexList(pkrel);
foreach(indexoidscan, indexoidlist)
{
Oid indexoid = lfirsti(indexoidscan);
HeapTuple indexTuple;
indexTuple = SearchSysCacheTuple(INDEXRELID,
ObjectIdGetDatum(indexoid),
0, 0, 0);
if (!HeapTupleIsValid(indexTuple))
elog(ERROR, "transformFkeyGetPrimaryKey: index %u not found",
indexoid);
indexStruct = (Form_pg_index) GETSTRUCT(indexTuple);
if (indexStruct->indisprimary)
break;
indexStruct = NULL;
}
freeList(indexoidlist);
/* ----------
* Check that we found it
* ----------
*/
if (indexStruct == NULL)
elog(ERROR, "PRIMARY KEY for referenced table \"%s\" not found",
fkconstraint->pktable_name);
/* ----------
* Now build the list of PK attributes from the indkey definition
* using the attribute names of the PK relation descriptor
* ----------
*/
2000-01-10 06:20:26 +01:00
for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
{
int pkattno = indexStruct->indkey[i];
Ident *pkattr = makeNode(Ident);
pkattr->name = DatumGetCString(DirectFunctionCall1(nameout,
NameGetDatum(&(pkrel_attrs[pkattno - 1]->attname))));
pkattr->indirection = NIL;
pkattr->isRel = false;
fkconstraint->pk_attrs = lappend(fkconstraint->pk_attrs, pkattr);
}
heap_close(pkrel, AccessShareLock);
}
/*
* Preprocess a list of column constraint clauses
* to attach constraint attributes to their primary constraint nodes
* and detect inconsistent/misplaced constraint attributes.
*
* NOTE: currently, attributes are only supported for FOREIGN KEY primary
* constraints, but someday they ought to be supported for other constraints.
*/
static void
transformConstraintAttrs(List *constraintList)
{
Node *lastprimarynode = NULL;
bool saw_deferrability = false;
bool saw_initially = false;
List *clist;
foreach(clist, constraintList)
{
Node *node = lfirst(clist);
if (!IsA(node, Constraint))
{
lastprimarynode = node;
/* reset flags for new primary node */
saw_deferrability = false;
saw_initially = false;
}
else
{
Constraint *con = (Constraint *) node;
switch (con->contype)
{
case CONSTR_ATTR_DEFERRABLE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
elog(ERROR, "Misplaced DEFERRABLE clause");
if (saw_deferrability)
elog(ERROR, "Multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed");
saw_deferrability = true;
((FkConstraint *) lastprimarynode)->deferrable = true;
break;
case CONSTR_ATTR_NOT_DEFERRABLE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
elog(ERROR, "Misplaced NOT DEFERRABLE clause");
if (saw_deferrability)
elog(ERROR, "Multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed");
saw_deferrability = true;
((FkConstraint *) lastprimarynode)->deferrable = false;
if (saw_initially &&
((FkConstraint *) lastprimarynode)->initdeferred)
elog(ERROR, "INITIALLY DEFERRED constraint must be DEFERRABLE");
break;
case CONSTR_ATTR_DEFERRED:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
elog(ERROR, "Misplaced INITIALLY DEFERRED clause");
if (saw_initially)
elog(ERROR, "Multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed");
saw_initially = true;
((FkConstraint *) lastprimarynode)->initdeferred = true;
/*
* If only INITIALLY DEFERRED appears, assume
* DEFERRABLE
*/
if (!saw_deferrability)
((FkConstraint *) lastprimarynode)->deferrable = true;
else if (!((FkConstraint *) lastprimarynode)->deferrable)
elog(ERROR, "INITIALLY DEFERRED constraint must be DEFERRABLE");
break;
case CONSTR_ATTR_IMMEDIATE:
if (lastprimarynode == NULL ||
!IsA(lastprimarynode, FkConstraint))
elog(ERROR, "Misplaced INITIALLY IMMEDIATE clause");
if (saw_initially)
elog(ERROR, "Multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed");
saw_initially = true;
((FkConstraint *) lastprimarynode)->initdeferred = false;
break;
default:
/* Otherwise it's not an attribute */
lastprimarynode = node;
/* reset flags for new primary node */
saw_deferrability = false;
saw_initially = false;
break;
}
}
}
}
/*
* Special handling of type definition for a column
*/
static void
transformColumnType(ParseState *pstate, ColumnDef *column)
{
/*
* If the column doesn't have an explicitly specified typmod, check to
* see if we want to insert a default length.
*
* Note that we deliberately do NOT look at array or set information
* here; "numeric[]" needs the same default typmod as "numeric".
*/
if (column->typename->typmod == -1)
{
switch (typeTypeId(typenameType(column->typename->name)))
{
case BPCHAROID:
/* "char" -> "char(1)" */
column->typename->typmod = VARHDRSZ + 1;
break;
case NUMERICOID:
column->typename->typmod = VARHDRSZ +
((NUMERIC_DEFAULT_PRECISION << 16) | NUMERIC_DEFAULT_SCALE);
break;
}
}
}