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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 1.151 2000/07/15 00:01:41 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "catalog/catname.h"
#include "catalog/pg_index.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "parser/analyze.h"
#include "parser/parse.h"
#include "parser/parse_agg.h"
#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"
void CheckSelectForUpdate(Query *qry); /* no points for style... */
static Query *transformStmt(ParseState *pstate, Node *stmt);
static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt);
static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt);
static Query *transformIndexStmt(ParseState *pstate, IndexStmt *stmt);
static Query *transformExtendStmt(ParseState *pstate, ExtendStmt *stmt);
static Query *transformRuleStmt(ParseState *query, RuleStmt *stmt);
static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt);
static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt);
static Query *transformCursorStmt(ParseState *pstate, SelectStmt *stmt);
static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt);
static Query *transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt);
static void transformForUpdate(Query *qry, List *forUpdate);
static void transformFkeyGetPrimaryKey(FkConstraint *fkconstraint);
static void transformConstraintAttrs(List *constraintList);
static void transformColumnType(ParseState *pstate, ColumnDef *column);
/* kluge to return extra info from transformCreateStmt() */
static List *extras_before;
static List *extras_after;
/*
* 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)
{
List *result = NIL;
ParseState *pstate;
Query *parsetree;
while (pl != NIL)
{
extras_before = extras_after = NIL;
pstate = make_parsestate(parentParseState);
parsetree = transformStmt(pstate, lfirst(pl));
if (pstate->p_target_relation != NULL)
heap_close(pstate->p_target_relation, AccessShareLock);
pstate->p_target_relation = NULL;
pstate->p_target_rangetblentry = NULL;
while (extras_before != NIL)
{
result = lappend(result,
transformStmt(pstate, lfirst(extras_before)));
if (pstate->p_target_relation != NULL)
heap_close(pstate->p_target_relation, AccessShareLock);
pstate->p_target_relation = NULL;
pstate->p_target_rangetblentry = NULL;
extras_before = lnext(extras_before);
}
result = lappend(result, parsetree);
while (extras_after != NIL)
{
result = lappend(result,
transformStmt(pstate, lfirst(extras_after)));
if (pstate->p_target_relation != NULL)
heap_close(pstate->p_target_relation, AccessShareLock);
pstate->p_target_relation = NULL;
pstate->p_target_rangetblentry = NULL;
extras_after = lnext(extras_after);
}
pfree(pstate);
pl = lnext(pl);
}
return result;
}
/*
* 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
*------------------------
*/
case T_InsertStmt:
result = transformInsertStmt(pstate, (InsertStmt *) parseTree);
break;
case T_DeleteStmt:
result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree);
break;
case T_UpdateStmt:
result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree);
break;
case T_SelectStmt:
if (!((SelectStmt *) parseTree)->portalname)
{
result = transformSelectStmt(pstate, (SelectStmt *) parseTree);
result->limitOffset = ((SelectStmt *) parseTree)->limitOffset;
result->limitCount = ((SelectStmt *) parseTree)->limitCount;
}
else
result = transformCursorStmt(pstate, (SelectStmt *) parseTree);
break;
default:
/*
* other statments don't require any transformation-- just
* return the original parsetree, 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;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs)
parseCheckAggregates(pstate, qry);
return (Query *) qry;
}
/*
* transformInsertStmt -
* transform an Insert Statement
*/
static Query *
transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
{
Query *qry = makeNode(Query);
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);
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);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
/*
* The INSERT INTO ... SELECT ... could have a UNION in child, so
* unionClause may be false
*/
qry->unionall = stmt->unionall;
/*
* Just hand through the unionClause and intersectClause. We will
* handle it in the function Except_Intersect_Rewrite()
*/
qry->unionClause = stmt->unionClause;
qry->intersectClause = stmt->intersectClause;
/*
* Now we are done with SELECT-like processing, and can get on with
* transforming the target list to match the INSERT target columns.
*
* In particular, it's time to add the INSERT target to the rangetable.
* (We didn't want it there until now since it shouldn't be visible in
* the SELECT part.)
*/
setTargetTable(pstate, stmt->relname, 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)),
0, 0, false),
stringToNode(defval[ndef].adbin));
qry->targetList = lappend(qry->targetList, te);
/*
* Make sure the value is coerced to the target column type
* (might not be right type if it's not a constant!)
*/
updateTargetListEntry(pstate, te, te->resdom->resname, attrno,
NIL);
}
}
if (stmt->forUpdate != NULL)
transformForUpdate(qry, stmt->forUpdate);
/* in case of subselects in default clauses... */
qry->hasSubLinks = pstate->p_hasSubLinks;
return (Query *) qry;
}
/*
* makeObjectName()
*
* Create a name for an implicitly created index, sequence, constraint, etc.
*
* The parameters are: the original table name, the original field name, and
* a "type" string (such as "seq" or "pkey"). The field name and/or type
* can be NULL if not relevant.
*
* The result is a palloc'd string.
*
* The basic result we want is "name1_name2_type", omitting "_name2" or
* "_type" when those parameters are NULL. However, we must generate
* a name with less than NAMEDATALEN characters! So, we truncate one or
* both names if necessary to make a short-enough string. The type part
* is never truncated (so it had better be reasonably short).
*
* To reduce the probability of collisions, we might someday add more
* smarts to this routine, like including some "hash" characters computed
* from the truncated characters. Currently it seems best to keep it simple,
* so that the generated names are easily predictable by a person.
*/
static char *
makeObjectName(char *name1, char *name2, char *typename)
{
char *name;
int overhead = 0; /* chars needed for type and underscores */
int availchars; /* chars available for name(s) */
int name1chars; /* chars allocated to name1 */
int name2chars; /* chars allocated to name2 */
int ndx;
name1chars = strlen(name1);
if (name2)
{
name2chars = strlen(name2);
overhead++; /* allow for separating underscore */
}
else
name2chars = 0;
if (typename)
overhead += strlen(typename) + 1;
availchars = NAMEDATALEN - 1 - overhead;
/*
* If we must truncate, preferentially truncate the longer name. This
* logic could be expressed without a loop, but it's simple and
* obvious as a loop.
*/
while (name1chars + name2chars > availchars)
{
if (name1chars > name2chars)
name1chars--;
else
name2chars--;
}
/* Now construct the string using the chosen lengths */
name = palloc(name1chars + name2chars + overhead + 1);
strncpy(name, name1, name1chars);
ndx = name1chars;
if (name2)
{
name[ndx++] = '_';
strncpy(name + ndx, name2, name2chars);
ndx += name2chars;
}
if (typename)
{
name[ndx++] = '_';
strcpy(name + ndx, typename);
}
else
name[ndx] = '\0';
return name;
}
static char *
CreateIndexName(char *table_name, char *column_name, char *label, List *indices)
{
int pass = 0;
char *iname = NULL;
List *ilist;
char typename[NAMEDATALEN];
/*
* The type name for makeObjectName is label, or labelN if that's
* necessary to prevent collisions among multiple indexes for the same
* table. Note there is no check for collisions with already-existing
* indexes; this ought to be rethought someday.
*/
strcpy(typename, label);
for (;;)
{
iname = makeObjectName(table_name, column_name, typename);
foreach(ilist, indices)
{
IndexStmt *index = lfirst(ilist);
if (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);
}
return iname;
}
/*
* transformCreateStmt -
* transforms the "create table" statement
* SQL92 allows constraints to be scattered all over, so thumb through
* the columns and collect all constraints into one place.
* If there are any implied indices (e.g. UNIQUE or PRIMARY KEY)
* then expand those into multiple IndexStmt blocks.
* - thomas 1997-12-02
*/
static Query *
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)
{
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);
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);
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)
|| (constraint->contype == CONSTR_UNIQUE));
index = makeNode(IndexStmt);
index->unique = TRUE;
index->primary = (constraint->contype == CONSTR_PRIMARY ? TRUE : FALSE);
if (index->primary)
{
if (pkey != NULL)
elog(ERROR, "CREATE TABLE/PRIMARY KEY multiple primary keys"
" for table '%s' are not allowed", stmt->relname);
pkey = (IndexStmt *) index;
}
if (constraint->name != NULL)
index->idxname = pstrdup(constraint->name);
else if (constraint->contype == CONSTR_PRIMARY)
index->idxname = makeObjectName(stmt->relname, NULL, "pkey");
else
index->idxname = NULL;
index->relname = stmt->relname;
index->accessMethod = "btree";
index->indexParams = NIL;
index->withClause = NIL;
index->whereClause = NULL;
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;
/* different names? then no match... */
if (strcmp(iname, pname) != 0)
{
keep = TRUE;
break;
}
pcols = lnext(pcols);
icols = lnext(icols);
}
}
if (keep)
ilist = lappend(ilist, index);
dlist = lnext(dlist);
}
}
dlist = ilist;
while (dlist != NIL)
{
index = lfirst(dlist);
elog(NOTICE, "CREATE TABLE/%s will create implicit index '%s' for table '%s'",
(index->primary ? "PRIMARY KEY" : "UNIQUE"),
index->idxname, stmt->relname);
dlist = lnext(dlist);
}
q->utilityStmt = (Node *) stmt;
extras_before = blist;
extras_after = ilist;
/*
* 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>";
/*
* 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);
}
}
/*
* 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, id->name);
fk_attr = lnext(fk_attr);
pk_attr = lnext(pk_attr);
}
extras_after = lappend(extras_after, (Node *) fk_trigger);
}
}
return q;
} /* transformCreateStmt() */
/*
* transformIndexStmt -
* transforms the qualification of the index statement
*/
static Query *
transformIndexStmt(ParseState *pstate, IndexStmt *stmt)
{
Query *qry;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/* take care of the where clause */
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
qry->hasSubLinks = pstate->p_hasSubLinks;
stmt->rangetable = pstate->p_rtable;
qry->utilityStmt = (Node *) stmt;
return qry;
}
/*
* transformExtendStmt -
* transform the qualifications of the Extend Index Statement
*
*/
static Query *
transformExtendStmt(ParseState *pstate, ExtendStmt *stmt)
{
Query *qry;
qry = makeNode(Query);
qry->commandType = CMD_UTILITY;
/* take care of the where clause */
stmt->whereClause = transformWhereClause(pstate, stmt->whereClause);
qry->hasSubLinks = pstate->p_hasSubLinks;
stmt->rangetable = pstate->p_rtable;
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)
{
Query *qry;
Query *action;
List *actions;
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);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->utilityStmt = (Node *) stmt;
return qry;
}
/*
* transformSelectStmt -
* transforms a Select Statement
*
*/
static Query *
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;
qry->hasAggs = pstate->p_hasAggs;
if (pstate->p_hasAggs || qry->groupClause || qry->havingQual)
parseCheckAggregates(pstate, qry);
/*
* The INSERT INTO ... SELECT ... could have a UNION in child, so
* unionClause may be false
*/
qry->unionall = stmt->unionall;
/*
* Just hand through the unionClause and intersectClause. We will
* handle it in the function Except_Intersect_Rewrite()
*/
qry->unionClause = stmt->unionClause;
qry->intersectClause = stmt->intersectClause;
qry->rtable = pstate->p_rtable;
if (stmt->forUpdate != NULL)
transformForUpdate(qry, stmt->forUpdate);
return (Query *) qry;
}
/*
* transformUpdateStmt -
* transforms an update statement
*
*/
static Query *
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);
qry->hasSubLinks = pstate->p_hasSubLinks;
qry->rtable = pstate->p_rtable;
qry->resultRelation = refnameRangeTablePosn(pstate, stmt->relname, NULL);
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 *
transformCursorStmt(ParseState *pstate, SelectStmt *stmt)
{
Query *qry;
qry = transformSelectStmt(pstate, stmt);
qry->into = stmt->portalname;
qry->isTemp = stmt->istemp;
qry->isPortal = TRUE;
qry->isBinary = stmt->binary; /* internal portal */
return qry;
}
/*
* 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, 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,
fkconstraint->constr_name);
fk_trigger->args = lappend(fk_trigger->args,
stmt->relname);
fk_trigger->args = lappend(fk_trigger->args,
fkconstraint->pktable_name);
fk_trigger->args = lappend(fk_trigger->args,
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, id->name);
id = (Ident *) lfirst(pk_attr);
fk_trigger->args = lappend(fk_trigger->args, 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;
}
/* This function steps through the tree
* built up by the select_w_o_sort rule
* and builds a list of all SelectStmt Nodes found
* The built up list is handed back in **select_list.
* If one of the SelectStmt Nodes has the 'unionall' flag
* set to true *unionall_present hands back 'true' */
void
create_select_list(Node *ptr, List **select_list, bool *unionall_present)
{
if (IsA(ptr, SelectStmt))
{
*select_list = lappend(*select_list, ptr);
if (((SelectStmt *) ptr)->unionall == TRUE)
*unionall_present = TRUE;
return;
}
/* 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);
}
/* Changes the A_Expr Nodes to Expr Nodes and exchanges ANDs and ORs.
* The reason for the exchange is easy: We implement INTERSECTs and EXCEPTs
* by rewriting these queries to semantically equivalent queries that use
* IN and NOT IN subselects. To be able to use all three operations
* (UNIONs INTERSECTs and EXCEPTs) in one complex query we have to
* translate the queries into Disjunctive Normal Form (DNF). Unfortunately
* there is no function 'dnfify' but there is a function 'cnfify'
* which produces DNF when we exchange ANDs and ORs before calling
* 'cnfify' and exchange them back in the result.
*
* If an EXCEPT or INTERSECT is present *intersect_present
* hands back 'true' */
Node *
A_Expr_to_Expr(Node *ptr, bool *intersect_present)
{
Node *result = NULL;
switch (nodeTag(ptr))
{
case T_A_Expr:
{
A_Expr *a = (A_Expr *) ptr;
switch (a->oper)
{
case AND:
{
Expr *expr = makeNode(Expr);
Node *lexpr = A_Expr_to_Expr(((A_Expr *) ptr)->lexpr, intersect_present);
Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
*intersect_present = TRUE;
expr->typeOid = BOOLOID;
expr->opType = OR_EXPR;
expr->args = makeList(lexpr, rexpr, -1);
result = (Node *) expr;
break;
}
case OR:
{
Expr *expr = makeNode(Expr);
Node *lexpr = A_Expr_to_Expr(((A_Expr *) ptr)->lexpr, intersect_present);
Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
expr->typeOid = BOOLOID;
expr->opType = AND_EXPR;
expr->args = makeList(lexpr, rexpr, -1);
result = (Node *) expr;
break;
}
case NOT:
{
Expr *expr = makeNode(Expr);
Node *rexpr = A_Expr_to_Expr(((A_Expr *) ptr)->rexpr, intersect_present);
expr->typeOid = BOOLOID;
expr->opType = NOT_EXPR;
expr->args = makeList(rexpr, -1);
result = (Node *) expr;
break;
}
}
break;
}
default:
result = ptr;
}
return result;
}
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)
elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause");
if (qry->groupClause != NIL)
elog(ERROR, "SELECT FOR UPDATE is not allowed with GROUP BY clause");
if (qry->hasAggs)
elog(ERROR, "SELECT FOR UPDATE is not allowed with AGGREGATE");
}
static void
transformForUpdate(Query *qry, List *forUpdate)
{
List *rowMark = NULL;
RowMark *newrm;
List *l;
Index i;
CheckSelectForUpdate(qry);
if (lfirst(forUpdate) == NULL) /* all tables */
{
i = 1;
foreach(l, qry->rtable)
{
newrm = makeNode(RowMark);
newrm->rti = i++;
newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
rowMark = lappend(rowMark, newrm);
}
qry->rowMark = nconc(qry->rowMark, rowMark);
return;
}
foreach(l, forUpdate)
{
char *relname = lfirst(l);
List *l2;
i = 1;
foreach(l2, qry->rtable)
{
if (strcmp(((RangeTblEntry *) lfirst(l2))->eref->relname, relname) == 0)
{
List *l3;
foreach(l3, rowMark)
{
if (((RowMark *) lfirst(l3))->rti == i) /* duplicate */
break;
}
if (l3 == NULL)
{
newrm = makeNode(RowMark);
newrm->rti = i;
newrm->info = ROW_MARK_FOR_UPDATE | ROW_ACL_FOR_UPDATE;
rowMark = lappend(rowMark, newrm);
}
break;
}
i++;
}
if (l2 == NULL)
elog(ERROR, "FOR UPDATE: relation '%s' not found in FROM clause",
relname);
}
qry->rowMark = rowMark;
}
/*
* 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
* ----------
*/
for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++)
{
int pkattno = indexStruct->indkey[i];
Ident *pkattr = makeNode(Ident);
pkattr->name = nameout(&(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;
}
}
}
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