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Allow WITH clauses to be attached to INSERT, UPDATE, DELETE statements.

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This is not the hoped-for facility of using INSERT/UPDATE/DELETE inside
a WITH, but rather the other way around.  It seems useful in its own
right anyway.

Note: catversion bumped because, although the contents of stored rules
might look compatible, there's actually a subtle semantic change.
A single Query containing a WITH and INSERT...VALUES now represents
writing the WITH before the INSERT, not before the VALUES.  While it's
not clear that that matters to anyone, it seems like a good idea to
have it cited in the git history for catversion.h.

Original patch by Marko Tiikkaja, with updating and cleanup by
Hitoshi Harada.
This commit is contained in:
Tom Lane
2010-10-15 19:53:59 -04:00
parent 6ab42ae367
commit 07f1264dda
14 changed files with 333 additions and 44 deletions
Download Patch File Download Diff File Expand all files Collapse all files

40
src/backend/parser/analyze.c
View File

@@ -283,6 +283,13 @@ transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt)
qry->commandType = CMD_DELETE;
/* process the WITH clause independently of all else */
if (stmt->withClause)
{
qry->hasRecursive = stmt->withClause->recursive;
qry->cteList = transformWithClause(pstate, stmt->withClause);
}
/* set up range table with just the result rel */
qry->resultRelation = setTargetTable(pstate, stmt->relation,
interpretInhOption(stmt->relation->inhOpt),
@@ -340,9 +347,19 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
ListCell *attnos;
ListCell *lc;
/* There can't be any outer WITH to worry about */
Assert(pstate->p_ctenamespace == NIL);
qry->commandType = CMD_INSERT;
pstate->p_is_insert = true;
/* process the WITH clause independently of all else */
if (stmt->withClause)
{
qry->hasRecursive = stmt->withClause->recursive;
qry->cteList = transformWithClause(pstate, stmt->withClause);
}
/*
* We have three cases to deal with: DEFAULT VALUES (selectStmt == NULL),
* VALUES list, or general SELECT input. We special-case VALUES, both for
@@ -376,8 +393,6 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
pstate->p_relnamespace = NIL;
sub_varnamespace = pstate->p_varnamespace;
pstate->p_varnamespace = NIL;
/* There can't be any outer WITH to worry about */
Assert(pstate->p_ctenamespace == NIL);
}
else
{
@@ -518,13 +533,6 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
List *exprsLists = NIL;
int sublist_length = -1;
/* process the WITH clause */
if (selectStmt->withClause)
{
qry->hasRecursive = selectStmt->withClause->recursive;
qry->cteList = transformWithClause(pstate, selectStmt->withClause);
}
foreach(lc, selectStmt->valuesLists)
{
List *sublist = (List *) lfirst(lc);
@@ -618,13 +626,6 @@ transformInsertStmt(ParseState *pstate, InsertStmt *stmt)
Assert(list_length(valuesLists) == 1);
/* process the WITH clause */
if (selectStmt->withClause)
{
qry->hasRecursive = selectStmt->withClause->recursive;
qry->cteList = transformWithClause(pstate, selectStmt->withClause);
}
/* Do basic expression transformation (same as a ROW() expr) */
exprList = transformExpressionList(pstate,
(List *) linitial(valuesLists));
@@ -1794,6 +1795,13 @@ transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt)
qry->commandType = CMD_UPDATE;
pstate->p_is_update = true;
/* process the WITH clause independently of all else */
if (stmt->withClause)
{
qry->hasRecursive = stmt->withClause->recursive;
qry->cteList = transformWithClause(pstate, stmt->withClause);
}
qry->resultRelation = setTargetTable(pstate, stmt->relation,
interpretInhOption(stmt->relation->inhOpt),
true,

40
src/backend/parser/gram.y
View File

@@ -433,7 +433,7 @@ static RangeVar *makeRangeVarFromAnyName(List *names, int position, core_yyscan_
%type <boolean> xml_whitespace_option
%type <node> common_table_expr
%type <with> with_clause
%type <with> with_clause opt_with_clause
%type <list> cte_list
%type <list> window_clause window_definition_list opt_partition_clause
@@ -7269,11 +7269,12 @@ DeallocateStmt: DEALLOCATE name
*****************************************************************************/
InsertStmt:
INSERT INTO qualified_name insert_rest returning_clause
opt_with_clause INSERT INTO qualified_name insert_rest returning_clause
{
$4->relation = $3;
$4->returningList = $5;
$$ = (Node *) $4;
$5->relation = $4;
$5->returningList = $6;
$5->withClause = $1;
$$ = (Node *) $5;
}
;
@@ -7329,14 +7330,15 @@ returning_clause:
*
*****************************************************************************/
DeleteStmt: DELETE_P FROM relation_expr_opt_alias
DeleteStmt: opt_with_clause DELETE_P FROM relation_expr_opt_alias
using_clause where_or_current_clause returning_clause
{
DeleteStmt *n = makeNode(DeleteStmt);
n->relation = $3;
n->usingClause = $4;
n->whereClause = $5;
n->returningList = $6;
n->relation = $4;
n->usingClause = $5;
n->whereClause = $6;
n->returningList = $7;
n->withClause = $1;
$$ = (Node *)n;
}
;
@@ -7391,18 +7393,19 @@ opt_nowait: NOWAIT { $$ = TRUE; }
*
*****************************************************************************/
UpdateStmt: UPDATE relation_expr_opt_alias
UpdateStmt: opt_with_clause UPDATE relation_expr_opt_alias
SET set_clause_list
from_clause
where_or_current_clause
returning_clause
{
UpdateStmt *n = makeNode(UpdateStmt);
n->relation = $2;
n->targetList = $4;
n->fromClause = $5;
n->whereClause = $6;
n->returningList = $7;
n->relation = $3;
n->targetList = $5;
n->fromClause = $6;
n->whereClause = $7;
n->returningList = $8;
n->withClause = $1;
$$ = (Node *)n;
}
;
@@ -7744,6 +7747,11 @@ common_table_expr: name opt_name_list AS select_with_parens
}
;
opt_with_clause:
with_clause { $$ = $1; }
| /*EMPTY*/ { $$ = NULL; }
;
into_clause:
INTO OptTempTableName
{

29
src/backend/parser/parse_utilcmd.c
View File

@@ -1867,6 +1867,35 @@ transformRuleStmt(RuleStmt *stmt, const char *queryString,
break;
}
/*
* OLD/NEW are not allowed in WITH queries, because they would
* amount to outer references for the WITH, which we disallow.
* However, they were already in the outer rangetable when we
* analyzed the query, so we have to check.
*
* Note that in the INSERT...SELECT case, we need to examine
* the CTE lists of both top_subqry and sub_qry.
*
* Note that we aren't digging into the body of the query
* looking for WITHs in nested sub-SELECTs. A WITH down there
* can legitimately refer to OLD/NEW, because it'd be an
* indirect-correlated outer reference.
*/
if (rangeTableEntry_used((Node *) top_subqry->cteList,
PRS2_OLD_VARNO, 0) ||
rangeTableEntry_used((Node *) sub_qry->cteList,
PRS2_OLD_VARNO, 0))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot refer to OLD within WITH query")));
if (rangeTableEntry_used((Node *) top_subqry->cteList,
PRS2_NEW_VARNO, 0) ||
rangeTableEntry_used((Node *) sub_qry->cteList,
PRS2_NEW_VARNO, 0))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("cannot refer to NEW within WITH query")));
/*
* For efficiency's sake, add OLD to the rule action's jointree
* only if it was actually referenced in the statement or qual.