From: Tom Lane Date: Thu, 10 Feb 2011 04:27:16 +0000 (-0500) Subject: Fix improper matching of resjunk column names for FOR UPDATE in subselect. X-Git-Tag: REL9_0_4~41 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=d5478c3391f8f1a243abbc3d9253aac3d6d3538e;p=pg-rex%2Fsyncrep.git Fix improper matching of resjunk column names for FOR UPDATE in subselect. Flattening of subquery range tables during setrefs.c could lead to the rangetable indexes in PlanRowMark nodes not matching up with the column names previously assigned to the corresponding resjunk ctid (resp. tableoid or wholerow) columns. Typical symptom would be either a "cannot extract system attribute from virtual tuple" error or an Assert failure. This wasn't a problem before 9.0 because we didn't support FOR UPDATE below the top query level, and so the final flattening could never renumber an RTE that was relevant to FOR UPDATE. Fix by using a plan-tree-wide unique number for each PlanRowMark to label the associated resjunk columns, so that the number need not change during flattening. Per report from David Johnston (though I'm darned if I can see how this got past initial testing of the relevant code). Back-patch to 9.0. --- diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c index 6d4a77328a..c477314efa 100644 --- a/src/backend/executor/execMain.c +++ b/src/backend/executor/execMain.c @@ -726,6 +726,7 @@ InitPlan(QueryDesc *queryDesc, int eflags) erm->relation = relation; erm->rti = rc->rti; erm->prti = rc->prti; + erm->rowmarkId = rc->rowmarkId; erm->markType = rc->markType; erm->noWait = rc->noWait; ItemPointerSetInvalid(&(erm->curCtid)); @@ -1373,23 +1374,29 @@ ExecBuildAuxRowMark(ExecRowMark *erm, List *targetlist) /* if child rel, need tableoid */ if (erm->rti != erm->prti) { - snprintf(resname, sizeof(resname), "tableoid%u", erm->prti); + snprintf(resname, sizeof(resname), "tableoid%u", erm->rowmarkId); aerm->toidAttNo = ExecFindJunkAttributeInTlist(targetlist, resname); + if (!AttributeNumberIsValid(aerm->toidAttNo)) + elog(ERROR, "could not find junk %s column", resname); } /* always need ctid for real relations */ - snprintf(resname, sizeof(resname), "ctid%u", erm->prti); + snprintf(resname, sizeof(resname), "ctid%u", erm->rowmarkId); aerm->ctidAttNo = ExecFindJunkAttributeInTlist(targetlist, resname); + if (!AttributeNumberIsValid(aerm->ctidAttNo)) + elog(ERROR, "could not find junk %s column", resname); } else { Assert(erm->markType == ROW_MARK_COPY); - snprintf(resname, sizeof(resname), "wholerow%u", erm->prti); + snprintf(resname, sizeof(resname), "wholerow%u", erm->rowmarkId); aerm->wholeAttNo = ExecFindJunkAttributeInTlist(targetlist, resname); + if (!AttributeNumberIsValid(aerm->wholeAttNo)) + elog(ERROR, "could not find junk %s column", resname); } return aerm; diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index 0b2aa3dfff..778c53063e 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -856,6 +856,7 @@ _copyPlanRowMark(PlanRowMark *from) COPY_SCALAR_FIELD(rti); COPY_SCALAR_FIELD(prti); + COPY_SCALAR_FIELD(rowmarkId); COPY_SCALAR_FIELD(markType); COPY_SCALAR_FIELD(noWait); COPY_SCALAR_FIELD(isParent); diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c index 032150e1bb..15a9aa2f93 100644 --- a/src/backend/nodes/outfuncs.c +++ b/src/backend/nodes/outfuncs.c @@ -756,6 +756,7 @@ _outPlanRowMark(StringInfo str, PlanRowMark *node) WRITE_UINT_FIELD(rti); WRITE_UINT_FIELD(prti); + WRITE_UINT_FIELD(rowmarkId); WRITE_ENUM_FIELD(markType, RowMarkType); WRITE_BOOL_FIELD(noWait); WRITE_BOOL_FIELD(isParent); @@ -1524,6 +1525,7 @@ _outPlannerGlobal(StringInfo str, PlannerGlobal *node) WRITE_NODE_FIELD(relationOids); WRITE_NODE_FIELD(invalItems); WRITE_UINT_FIELD(lastPHId); + WRITE_UINT_FIELD(lastRowMarkId); WRITE_BOOL_FIELD(transientPlan); } diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 45ba902fba..55206573c7 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -165,6 +165,7 @@ standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams) glob->relationOids = NIL; glob->invalItems = NIL; glob->lastPHId = 0; + glob->lastRowMarkId = 0; glob->transientPlan = false; /* Determine what fraction of the plan is likely to be scanned */ @@ -1852,6 +1853,7 @@ preprocess_rowmarks(PlannerInfo *root) newrc = makeNode(PlanRowMark); newrc->rti = newrc->prti = rc->rti; + newrc->rowmarkId = ++(root->glob->lastRowMarkId); if (rc->forUpdate) newrc->markType = ROW_MARK_EXCLUSIVE; else @@ -1877,6 +1879,7 @@ preprocess_rowmarks(PlannerInfo *root) newrc = makeNode(PlanRowMark); newrc->rti = newrc->prti = i; + newrc->rowmarkId = ++(root->glob->lastRowMarkId); /* real tables support REFERENCE, anything else needs COPY */ if (rte->rtekind == RTE_RELATION) newrc->markType = ROW_MARK_REFERENCE; diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c index 70be2e66f2..2618ef14a8 100644 --- a/src/backend/optimizer/plan/setrefs.c +++ b/src/backend/optimizer/plan/setrefs.c @@ -252,7 +252,7 @@ set_plan_references(PlannerGlobal *glob, Plan *plan, newrc = (PlanRowMark *) palloc(sizeof(PlanRowMark)); memcpy(newrc, rc, sizeof(PlanRowMark)); - /* adjust indexes */ + /* adjust indexes ... but *not* the rowmarkId */ newrc->rti += rtoffset; newrc->prti += rtoffset; diff --git a/src/backend/optimizer/prep/preptlist.c b/src/backend/optimizer/prep/preptlist.c index 7a09d1f830..425d80c624 100644 --- a/src/backend/optimizer/prep/preptlist.c +++ b/src/backend/optimizer/prep/preptlist.c @@ -132,7 +132,7 @@ preprocess_targetlist(PlannerInfo *root, List *tlist) TIDOID, -1, 0); - snprintf(resname, sizeof(resname), "ctid%u", rc->rti); + snprintf(resname, sizeof(resname), "ctid%u", rc->rowmarkId); tle = makeTargetEntry((Expr *) var, list_length(tlist) + 1, pstrdup(resname), @@ -147,7 +147,7 @@ preprocess_targetlist(PlannerInfo *root, List *tlist) OIDOID, -1, 0); - snprintf(resname, sizeof(resname), "tableoid%u", rc->rti); + snprintf(resname, sizeof(resname), "tableoid%u", rc->rowmarkId); tle = makeTargetEntry((Expr *) var, list_length(tlist) + 1, pstrdup(resname), @@ -161,7 +161,7 @@ preprocess_targetlist(PlannerInfo *root, List *tlist) var = makeWholeRowVar(rt_fetch(rc->rti, range_table), rc->rti, 0); - snprintf(resname, sizeof(resname), "wholerow%u", rc->rti); + snprintf(resname, sizeof(resname), "wholerow%u", rc->rowmarkId); tle = makeTargetEntry((Expr *) var, list_length(tlist) + 1, pstrdup(resname), diff --git a/src/backend/optimizer/prep/prepunion.c b/src/backend/optimizer/prep/prepunion.c index 35f9f980e9..cabc93d5df 100644 --- a/src/backend/optimizer/prep/prepunion.c +++ b/src/backend/optimizer/prep/prepunion.c @@ -1288,6 +1288,7 @@ expand_inherited_rtentry(PlannerInfo *root, RangeTblEntry *rte, Index rti) newrc->rti = childRTindex; newrc->prti = rti; + newrc->rowmarkId = oldrc->rowmarkId; newrc->markType = oldrc->markType; newrc->noWait = oldrc->noWait; newrc->isParent = false; diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h index fda44255b0..ac0de093f1 100644 --- a/src/include/nodes/execnodes.h +++ b/src/include/nodes/execnodes.h @@ -417,6 +417,7 @@ typedef struct ExecRowMark Relation relation; /* opened and suitably locked relation */ Index rti; /* its range table index */ Index prti; /* parent range table index, if child */ + Index rowmarkId; /* unique identifier for resjunk columns */ RowMarkType markType; /* see enum in nodes/plannodes.h */ bool noWait; /* NOWAIT option */ ItemPointerData curCtid; /* ctid of currently locked tuple, if any */ diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h index e14257932e..729e35557d 100644 --- a/src/include/nodes/plannodes.h +++ b/src/include/nodes/plannodes.h @@ -701,7 +701,11 @@ typedef enum RowMarkType * The tableoid column is only present for an inheritance hierarchy. * When markType == ROW_MARK_COPY, there is instead a single column named * wholerow%u whole-row value of relation - * In all three cases, %u represents the parent rangetable index (prti). + * In all three cases, %u represents the rowmark ID number (rowmarkId). + * This number is unique within a plan tree, except that child relation + * entries copy their parent's rowmarkId. (Assigning unique numbers + * means we needn't renumber rowmarkIds when flattening subqueries, which + * would require finding and renaming the resjunk columns as well.) * Note this means that all tables in an inheritance hierarchy share the * same resjunk column names. However, in an inherited UPDATE/DELETE the * columns could have different physical column numbers in each subplan. @@ -711,6 +715,7 @@ typedef struct PlanRowMark NodeTag type; Index rti; /* range table index of markable relation */ Index prti; /* range table index of parent relation */ + Index rowmarkId; /* unique identifier for resjunk columns */ RowMarkType markType; /* see enum above */ bool noWait; /* NOWAIT option */ bool isParent; /* true if this is a "dummy" parent entry */ diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index a3678a5b58..f109a1de52 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -82,6 +82,8 @@ typedef struct PlannerGlobal Index lastPHId; /* highest PlaceHolderVar ID assigned */ + Index lastRowMarkId; /* highest PlanRowMark ID assigned */ + bool transientPlan; /* redo plan when TransactionXmin changes? */ } PlannerGlobal;