From: Andrew Gierth Date: Tue, 24 Nov 2020 20:58:32 +0000 (+0000) Subject: Properly check index mark/restore in ExecSupportsMarkRestore. X-Git-Tag: REL9_6_21~70 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6402afd9865e3218b1f3835108a1e156157b6e08;p=thirdparty%2Fpostgresql.git Properly check index mark/restore in ExecSupportsMarkRestore. Previously this code assumed that all IndexScan nodes supported mark/restore, which is not true since it depends on optional index AM support functions. This could lead to errors about missing support functions in rare edge cases of mergejoins with no sort keys, where an unordered non-btree index scan was placed on the inner path without a protecting Materialize node. (Normally, the fact that merge join requires ordered input would avoid this error.) Backpatch all the way since this bug is ancient. Per report from Eugen Konkov on irc. Discussion: https://postgr.es/m/87o8jn50be.fsf@news-spur.riddles.org.uk --- diff --git a/src/backend/executor/execAmi.c b/src/backend/executor/execAmi.c index 2587ef70462..27690ec2fb3 100644 --- a/src/backend/executor/execAmi.c +++ b/src/backend/executor/execAmi.c @@ -394,6 +394,11 @@ ExecSupportsMarkRestore(Path *pathnode) { case T_IndexScan: case T_IndexOnlyScan: + /* + * Not all index types support mark/restore. + */ + return castNode(IndexPath, pathnode)->indexinfo->amcanmarkpos; + case T_Material: case T_Sort: return true; diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index 945e6e61047..72fc75d5339 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -242,6 +242,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent, info->amsearchnulls = amroutine->amsearchnulls; info->amhasgettuple = (amroutine->amgettuple != NULL); info->amhasgetbitmap = (amroutine->amgetbitmap != NULL); + info->amcanmarkpos = (amroutine->ammarkpos != NULL && + amroutine->amrestrpos != NULL); info->amcostestimate = amroutine->amcostestimate; Assert(info->amcostestimate != NULL); diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 7b215f0075e..fa68b99a0f0 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -620,6 +620,7 @@ typedef struct IndexOptInfo bool amsearchnulls; /* can AM search for NULL/NOT NULL entries? */ bool amhasgettuple; /* does AM have amgettuple interface? */ bool amhasgetbitmap; /* does AM have amgetbitmap interface? */ + bool amcanmarkpos; /* does AM support mark/restore? */ /* Rather than include amapi.h here, we declare amcostestimate like this */ void (*amcostestimate) (); /* AM's cost estimator */ } IndexOptInfo;