database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-11 10:01:57 +03:00
Code Activity

Fix PlanRowMark/ExecRowMark structures to handle inheritance correctly.

Browse Source 
In an inherited UPDATE/DELETE, each target table has its own subplan,
because it might have a column set different from other targets.  This
means that the resjunk columns we add to support EvalPlanQual might be
at different physical column numbers in each subplan.  The EvalPlanQual
rewrite I did for 9.0 failed to account for this, resulting in possible
misbehavior or even crashes during concurrent updates to the same row,
as seen in a recent report from Gordon Shannon.  Revise the data structure
so that we track resjunk column numbers separately for each subplan.

I also chose to move responsibility for identifying the physical column
numbers back to executor startup, instead of assuming that numbers derived
during preprocess_targetlist would stay valid throughout subsequent
massaging of the plan.  That's a bit slower, so we might want to consider
undoing it someday; but it would complicate the patch considerably and
didn't seem justifiable in a bug fix that has to be back-patched to 9.0.
This commit is contained in:
Tom Lane
2011-01-12 20:47:02 -05:00
parent 7a32ff9732
commit d487afbb81
12 changed files with 193 additions and 123 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/backend/optimizer/plan/planner.c
View File

@ -1929,10 +1929,6 @@ preprocess_rowmarks(PlannerInfo *root)
newrc->markType = ROW_MARK_SHARE;
newrc->noWait = rc->noWait;
newrc->isParent = false;
/* attnos will be assigned in preprocess_targetlist */
newrc->ctidAttNo = InvalidAttrNumber;
newrc->toidAttNo = InvalidAttrNumber;
newrc->wholeAttNo = InvalidAttrNumber;
prowmarks = lappend(prowmarks, newrc);
}
@ -1959,10 +1955,6 @@ preprocess_rowmarks(PlannerInfo *root)
newrc->markType = ROW_MARK_COPY;
newrc->noWait = false; /* doesn't matter */
newrc->isParent = false;
/* attnos will be assigned in preprocess_targetlist */
newrc->ctidAttNo = InvalidAttrNumber;
newrc->toidAttNo = InvalidAttrNumber;
newrc->wholeAttNo = InvalidAttrNumber;
prowmarks = lappend(prowmarks, newrc);
}