Fix bogus test for hypothetical indexes in get_actual_variable_range().

tglsfdc · tglsfdc · commit 7422e0081d04 · 2011-02-16T19:24:50.000-05:00
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
@@ -1611,10 +1611,12 @@ _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
@@ -275,6 +275,7 @@ 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
@@ -4555,10 +4555,10 @@ 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
@@ -471,6 +471,8 @@ 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? */
+	/* added in 9.0.4: */
+	bool		hypothetical;	/* true if index doesn't really exist */
 } IndexOptInfo;
 
 
