Fix bogus test for hypothetical indexes in get_actual_variable_range().

That function was supposing that indexoid == 0 for a hypothetical index,
but that is not likely to be true in any non-toy implementation of an index
adviser, since assigning a fake OID is the only way to know at EXPLAIN time
which hypothetical index got selected.  Fix by adding a flag to
IndexOptInfo to mark hypothetical indexes.  Back-patch to 9.0 where
get_actual_variable_range() was added.

Gurjeet Singh

diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 5c943bc..192c042 100644 (file)
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -1700,10 +1700,12 @@ _outIndexOptInfo(StringInfo str, IndexOptInfo *node)
        WRITE_UINT_FIELD(pages);
        WRITE_FLOAT_FIELD(tuples, "%.0f");
        WRITE_INT_FIELD(ncolumns);
+       WRITE_OID_FIELD(relam);
        WRITE_NODE_FIELD(indexprs);
        WRITE_NODE_FIELD(indpred);
        WRITE_BOOL_FIELD(predOK);
        WRITE_BOOL_FIELD(unique);
+       WRITE_BOOL_FIELD(hypothetical);
 }
 
 static void

diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 1f79ba2..40df626 100644 (file)
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -316,6 +316,7 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
                                ChangeVarNodes((Node *) info->indpred, 1, varno, 0);
                        info->predOK = false;           /* set later in indxpath.c */
                        info->unique = index->indisunique;
+                       info->hypothetical = false;
 
                        /*
                         * Estimate the index size.  If it's not a partial index, we lock

diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c
index b3299b5..f10110b 100644 (file)
--- a/src/backend/utils/adt/selfuncs.c
+++ b/src/backend/utils/adt/selfuncs.c
@@ -4562,10 +4562,10 @@ get_actual_variable_range(PlannerInfo *root, VariableStatData *vardata,
                        continue;
 
                /*
-                * The index list might include fictitious indexes inserted by a
+                * The index list might include hypothetical indexes inserted by a
                 * get_relation_info hook --- don't try to access them.
                 */
-               if (!OidIsValid(index->indexoid))
+               if (index->hypothetical)
                        continue;
 
                /*

diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h
index 49ce441..6f51b6c 100644 (file)
--- a/src/include/nodes/relation.h
+++ b/src/include/nodes/relation.h
@@ -455,7 +455,7 @@ typedef struct IndexOptInfo
        int                     ncolumns;               /* number of columns in index */
        Oid                *opfamily;           /* OIDs of operator families for columns */
        int                *indexkeys;          /* column numbers of index's keys, or 0 */
-       Oid                *indexcollations;/* OIDs of the collations of the index columns */
+       Oid                *indexcollations;    /* OIDs of collations of index columns */
        Oid                *opcintype;          /* OIDs of opclass declared input data types */
        Oid                *sortopfamily;       /* OIDs of btree opfamilies, if orderable */
        bool       *reverse_sort;       /* is sort order descending? */
@@ -469,6 +469,7 @@ typedef struct IndexOptInfo
 
        bool            predOK;                 /* true if predicate matches query */
        bool            unique;                 /* true if a unique index */
+       bool            hypothetical;   /* true if index doesn't really exist */
        bool            amcanorderbyop; /* does AM support order by operator result? */
        bool            amoptionalkey;  /* can query omit key for the first column? */
        bool            amsearchnulls;  /* can AM search for NULL/NOT NULL entries? */