Refactor insert select planner to exclude identity columns from both insert and select target lists

m3hm3t/issue_7887
Mehmet Yilmaz 2025-02-28 15:10:38 +00:00
parent 67b390ee3e
commit f4835b7dbb
1 changed files with 50 additions and 32 deletions

View File

@ -1435,12 +1435,8 @@ CreateNonPushableInsertSelectPlan(uint64 planId, Query *parse, ParamListInfo bou
PrepareInsertSelectForCitusPlanner(insertSelectQuery);
/*
* The insertTargetList are the columns we plan to insert into the target table.
* For partial inserts, it might incorrectly include the identity column if
* some rewriting logic added it. We'll fix that below.
*/
List *insertTargetList = insertSelectQuery->targetList;
/* get the SELECT query (may have changed after PrepareInsertSelectForCitusPlanner) */
Query *selectQuery = selectRte->subquery;
/*
* 1) Open the target relation to inspect its attributes and detect identity columns.
@ -1448,51 +1444,73 @@ CreateNonPushableInsertSelectPlan(uint64 planId, Query *parse, ParamListInfo bou
Relation targetRel = RelationIdGetRelation(targetRelationId);
if (RelationIsValid(targetRel))
{
/* We'll build a new list of TLEs that excludes identity columns if user omitted them. */
List *newTargetList = NIL;
ListCell *lc = NULL;
foreach(lc, insertTargetList)
ListCell *lcInsert = NULL;
// ListCell *lcSelect = list_head(selectQuery->targetList);
/* We'll build new lists for both sides */
List *newInsertTList = NIL;
List *newSelectTList = NIL;
int insertIndex = 0;
foreach(lcInsert, insertSelectQuery->targetList)
{
TargetEntry *tle = (TargetEntry *) lfirst(lc);
TargetEntry *insertTle = (TargetEntry *) lfirst(lcInsert);
insertIndex++;
/* Get the corresponding TLE from the SELECT by position or resno */
TargetEntry *selectTle = NULL;
/*
* resno is 1-based attribute number: if we have 3 columns in table, they
* correspond to resno=1..3. Make sure attno is in range before we do anything.
*/
int attno = tle->resno;
* If your plan is guaranteed to keep them in the same order, you can
* do "selectTle = (TargetEntry *) list_nth(selectQuery->targetList, insertIndex - 1)".
*
* Alternatively, if you rely on resno alignment, you'd find the TLE with resno==insertTle->resno.
* For simplicity, let's assume same ordering:
*/
selectTle = (TargetEntry *) list_nth(selectQuery->targetList, insertIndex - 1);
/*
* Check if the insertTle is an identity column that the user didn't supply,
* e.g. by checking 'attr->attidentity == ATTRIBUTE_IDENTITY_ALWAYS' etc.
* If we skip it, also skip the SELECT TLE at the same position.
*/
int attno = insertTle->resno;
if (attno > 0 && attno <= targetRel->rd_att->natts)
{
Form_pg_attribute attr = TupleDescAttr(targetRel->rd_att, attno - 1);
/*
* If 'attr->attidentity' is 'a' or 'd' => It's an identity column.
* If the user hasn't explicitly specified a value (which is presumably
* indicated by something in the parse tree?), we remove or convert
* the TLE to a default.
*/
bool userSpecifiedValue = CheckIfUserSpecifiedValue(tle, parse);
* If 'attr->attidentity' is 'a' or 'd' => It's an identity column.
* If the user hasn't explicitly specified a value (which is presumably
* indicated by something in the parse tree?), we remove or convert
* the TLE to a default.
*/
// bool userSpecifiedValue = CheckIfUserSpecifiedValue(tle, parse);
bool userSpecifiedValue = false;
if ((attr->attidentity == ATTRIBUTE_IDENTITY_ALWAYS ||
attr->attidentity == ATTRIBUTE_IDENTITY_BY_DEFAULT) &&
attr->attidentity == ATTRIBUTE_IDENTITY_BY_DEFAULT) &&
!userSpecifiedValue)
{
/* Skip adding TLE => effectively uses default identity generation */
continue;
}
}
/* If we get here, we keep the TLE. */
newTargetList = lappend(newTargetList, tle);
/* else keep both TLEs */
newInsertTList = lappend(newInsertTList, insertTle);
newSelectTList = lappend(newSelectTList, selectTle);
}
/* Update the plan's target list to the "cleaned" version */
insertSelectQuery->targetList = newTargetList;
/* Now we have 1:1 matching lists with the identity column removed from both sides */
insertSelectQuery->targetList = newInsertTList;
selectQuery->targetList = newSelectTList;
RelationClose(targetRel);
}
/* get the SELECT query (may have changed after PrepareInsertSelectForCitusPlanner) */
Query *selectQuery = selectRte->subquery;
/*
* Later we might need to call WrapTaskListForProjection(), which requires