CREATE INDEX ... INCLUDING (column[, ...])

Now indexes (but only B-tree for now) can contain "extra" column(s) which
doesn't participate in index structure, they are just stored in leaf
tuples. It allows to use index only scan by using single index instead
of two or more indexes.

Author: Anastasia Lubennikova with minor editorializing by me
Reviewers: David Rowley, Peter Geoghegan, Jeff Janes

1 files changed, 48 insertions, 35 deletions

diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index 432feefa609..b171ddb8cc6 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -521,7 +521,7 @@ RelationBuildTupleDesc(Relation relation)
 	/*
 	 * add attribute data to relation->rd_att
 	 */
-	need = relation->rd_rel->relnatts;
+	need = RelationGetNumberOfAttributes(relation);
 
 	while (HeapTupleIsValid(pg_attribute_tuple = systable_getnext(pg_attribute_scan)))
 	{
@@ -530,7 +530,7 @@ RelationBuildTupleDesc(Relation relation)
 		attp = (Form_pg_attribute) GETSTRUCT(pg_attribute_tuple);
 
 		if (attp->attnum <= 0 ||
-			attp->attnum > relation->rd_rel->relnatts)
+			attp->attnum > RelationGetNumberOfAttributes(relation))
 			elog(ERROR, "invalid attribute number %d for %s",
 				 attp->attnum, RelationGetRelationName(relation));
 
@@ -547,7 +547,7 @@ RelationBuildTupleDesc(Relation relation)
 			if (attrdef == NULL)
 				attrdef = (AttrDefault *)
 					MemoryContextAllocZero(CacheMemoryContext,
-										   relation->rd_rel->relnatts *
+										   RelationGetNumberOfAttributes(relation) *
 										   sizeof(AttrDefault));
 			attrdef[ndef].adnum = attp->attnum;
 			attrdef[ndef].adbin = NULL;
@@ -577,7 +577,7 @@ RelationBuildTupleDesc(Relation relation)
 	{
 		int			i;
 
-		for (i = 0; i < relation->rd_rel->relnatts; i++)
+		for (i = 0; i < RelationGetNumberOfAttributes(relation); i++)
 			Assert(relation->rd_att->attrs[i]->attcacheoff == -1);
 	}
 #endif
@@ -587,7 +587,7 @@ RelationBuildTupleDesc(Relation relation)
 	 * attribute: it must be zero.  This eliminates the need for special cases
 	 * for attnum=1 that used to exist in fastgetattr() and index_getattr().
 	 */
-	if (relation->rd_rel->relnatts > 0)
+	if (RelationGetNumberOfAttributes(relation) > 0)
 		relation->rd_att->attrs[0]->attcacheoff = 0;
 
 	/*
@@ -599,7 +599,7 @@ RelationBuildTupleDesc(Relation relation)
 
 		if (ndef > 0)			/* DEFAULTs */
 		{
-			if (ndef < relation->rd_rel->relnatts)
+			if (ndef < RelationGetNumberOfAttributes(relation))
 				constr->defval = (AttrDefault *)
 					repalloc(attrdef, ndef * sizeof(AttrDefault));
 			else
@@ -1205,7 +1205,8 @@ RelationInitIndexAccessInfo(Relation relation)
 	int2vector *indoption;
 	MemoryContext indexcxt;
 	MemoryContext oldcontext;
-	int			natts;
+	int			indnatts;
+	int			indnkeyatts;
 	uint16		amsupport;
 
 	/*
@@ -1235,10 +1236,11 @@ RelationInitIndexAccessInfo(Relation relation)
 	relation->rd_amhandler = aform->amhandler;
 	ReleaseSysCache(tuple);
 
-	natts = relation->rd_rel->relnatts;
-	if (natts != relation->rd_index->indnatts)
+	indnatts = RelationGetNumberOfAttributes(relation);
+	if (indnatts != IndexRelationGetNumberOfAttributes(relation))
 		elog(ERROR, "relnatts disagrees with indnatts for index %u",
 			 RelationGetRelid(relation));
+	indnkeyatts = IndexRelationGetNumberOfKeyAttributes(relation);
 
 	/*
 	 * Make the private context to hold index access info.  The reason we need
@@ -1264,14 +1266,14 @@ RelationInitIndexAccessInfo(Relation relation)
 	 * Allocate arrays to hold data
 	 */
 	relation->rd_opfamily = (Oid *)
-		MemoryContextAllocZero(indexcxt, natts * sizeof(Oid));
+		MemoryContextAllocZero(indexcxt, indnkeyatts * sizeof(Oid));
 	relation->rd_opcintype = (Oid *)
-		MemoryContextAllocZero(indexcxt, natts * sizeof(Oid));
+		MemoryContextAllocZero(indexcxt, indnkeyatts * sizeof(Oid));
 
 	amsupport = relation->rd_amroutine->amsupport;
 	if (amsupport > 0)
 	{
-		int			nsupport = natts * amsupport;
+		int			nsupport = indnatts * amsupport;
 
 		relation->rd_support = (RegProcedure *)
 			MemoryContextAllocZero(indexcxt, nsupport * sizeof(RegProcedure));
@@ -1285,10 +1287,10 @@ RelationInitIndexAccessInfo(Relation relation)
 	}
 
 	relation->rd_indcollation = (Oid *)
-		MemoryContextAllocZero(indexcxt, natts * sizeof(Oid));
+		MemoryContextAllocZero(indexcxt, indnatts * sizeof(Oid));
 
 	relation->rd_indoption = (int16 *)
-		MemoryContextAllocZero(indexcxt, natts * sizeof(int16));
+		MemoryContextAllocZero(indexcxt, indnatts * sizeof(int16));
 
 	/*
 	 * indcollation cannot be referenced directly through the C struct,
@@ -1301,7 +1303,7 @@ RelationInitIndexAccessInfo(Relation relation)
 							   &isnull);
 	Assert(!isnull);
 	indcoll = (oidvector *) DatumGetPointer(indcollDatum);
-	memcpy(relation->rd_indcollation, indcoll->values, natts * sizeof(Oid));
+	memcpy(relation->rd_indcollation, indcoll->values, indnatts * sizeof(Oid));
 
 	/*
 	 * indclass cannot be referenced directly through the C struct, because it
@@ -1322,7 +1324,7 @@ RelationInitIndexAccessInfo(Relation relation)
 	 */
 	IndexSupportInitialize(indclass, relation->rd_support,
 						   relation->rd_opfamily, relation->rd_opcintype,
-						   amsupport, natts);
+						   amsupport, indnkeyatts);
 
 	/*
 	 * Similarly extract indoption and copy it to the cache entry
@@ -1333,7 +1335,7 @@ RelationInitIndexAccessInfo(Relation relation)
 								 &isnull);
 	Assert(!isnull);
 	indoption = (int2vector *) DatumGetPointer(indoptionDatum);
-	memcpy(relation->rd_indoption, indoption->values, natts * sizeof(int16));
+	memcpy(relation->rd_indoption, indoption->values, indnatts * sizeof(int16));
 
 	/*
 	 * expressions, predicate, exclusion caches will be filled later
@@ -4394,16 +4396,25 @@ RelationGetIndexAttrBitmap(Relation relation, IndexAttrBitmapKind attrKind)
 		{
 			int			attrnum = indexInfo->ii_KeyAttrNumbers[i];
 
+			/*
+			 * Since we have covering indexes with non-key columns,
+			 * we must handle them accurately here. non-key columns
+			 * must be added into indexattrs, since they are in index,
+			 * and HOT-update shouldn't miss them.
+			 * Obviously, non-key columns couldn't be referenced by
+			 * foreign key or identity key. Hence we do not include
+			 * them into uindexattrs and idindexattrs bitmaps.
+			 */
 			if (attrnum != 0)
 			{
 				indexattrs = bms_add_member(indexattrs,
 							   attrnum - FirstLowInvalidHeapAttributeNumber);
 
-				if (isKey)
+				if (isKey && i < indexInfo->ii_NumIndexKeyAttrs)
 					uindexattrs = bms_add_member(uindexattrs,
 							   attrnum - FirstLowInvalidHeapAttributeNumber);
 
-				if (isIDKey)
+				if (isIDKey && i < indexInfo->ii_NumIndexKeyAttrs)
 					idindexattrs = bms_add_member(idindexattrs,
 							   attrnum - FirstLowInvalidHeapAttributeNumber);
 			}
@@ -4471,7 +4482,7 @@ RelationGetExclusionInfo(Relation indexRelation,
 						 Oid **procs,
 						 uint16 **strategies)
 {
-	int			ncols = indexRelation->rd_rel->relnatts;
+	int			indnkeyatts;
 	Oid		   *ops;
 	Oid		   *funcs;
 	uint16	   *strats;
@@ -4483,17 +4494,19 @@ RelationGetExclusionInfo(Relation indexRelation,
 	MemoryContext oldcxt;
 	int			i;
 
+	indnkeyatts = IndexRelationGetNumberOfKeyAttributes(indexRelation);
+
 	/* Allocate result space in caller context */
-	*operators = ops = (Oid *) palloc(sizeof(Oid) * ncols);
-	*procs = funcs = (Oid *) palloc(sizeof(Oid) * ncols);
-	*strategies = strats = (uint16 *) palloc(sizeof(uint16) * ncols);
+	*operators = ops = (Oid *) palloc(sizeof(Oid) * indnkeyatts);
+	*procs = funcs = (Oid *) palloc(sizeof(Oid) * indnkeyatts);
+	*strategies = strats = (uint16 *) palloc(sizeof(uint16) * indnkeyatts);
 
 	/* Quick exit if we have the data cached already */
 	if (indexRelation->rd_exclstrats != NULL)
 	{
-		memcpy(ops, indexRelation->rd_exclops, sizeof(Oid) * ncols);
-		memcpy(funcs, indexRelation->rd_exclprocs, sizeof(Oid) * ncols);
-		memcpy(strats, indexRelation->rd_exclstrats, sizeof(uint16) * ncols);
+		memcpy(ops, indexRelation->rd_exclops, sizeof(Oid) * indnkeyatts);
+		memcpy(funcs, indexRelation->rd_exclprocs, sizeof(Oid) * indnkeyatts);
+		memcpy(strats, indexRelation->rd_exclstrats, sizeof(uint16) * indnkeyatts);
 		return;
 	}
 
@@ -4542,12 +4555,12 @@ RelationGetExclusionInfo(Relation indexRelation,
 		arr = DatumGetArrayTypeP(val);	/* ensure not toasted */
 		nelem = ARR_DIMS(arr)[0];
 		if (ARR_NDIM(arr) != 1 ||
-			nelem != ncols ||
+			nelem != indnkeyatts ||
 			ARR_HASNULL(arr) ||
 			ARR_ELEMTYPE(arr) != OIDOID)
 			elog(ERROR, "conexclop is not a 1-D Oid array");
 
-		memcpy(ops, ARR_DATA_PTR(arr), sizeof(Oid) * ncols);
+		memcpy(ops, ARR_DATA_PTR(arr), sizeof(Oid) * indnkeyatts);
 	}
 
 	systable_endscan(conscan);
@@ -4558,7 +4571,7 @@ RelationGetExclusionInfo(Relation indexRelation,
 			 RelationGetRelationName(indexRelation));
 
 	/* We need the func OIDs and strategy numbers too */
-	for (i = 0; i < ncols; i++)
+	for (i = 0; i < indnkeyatts; i++)
 	{
 		funcs[i] = get_opcode(ops[i]);
 		strats[i] = get_op_opfamily_strategy(ops[i],
@@ -4571,12 +4584,12 @@ RelationGetExclusionInfo(Relation indexRelation,
 
 	/* Save a copy of the results in the relcache entry. */
 	oldcxt = MemoryContextSwitchTo(indexRelation->rd_indexcxt);
-	indexRelation->rd_exclops = (Oid *) palloc(sizeof(Oid) * ncols);
-	indexRelation->rd_exclprocs = (Oid *) palloc(sizeof(Oid) * ncols);
-	indexRelation->rd_exclstrats = (uint16 *) palloc(sizeof(uint16) * ncols);
-	memcpy(indexRelation->rd_exclops, ops, sizeof(Oid) * ncols);
-	memcpy(indexRelation->rd_exclprocs, funcs, sizeof(Oid) * ncols);
-	memcpy(indexRelation->rd_exclstrats, strats, sizeof(uint16) * ncols);
+	indexRelation->rd_exclops = (Oid *) palloc(sizeof(Oid) * indnkeyatts);
+	indexRelation->rd_exclprocs = (Oid *) palloc(sizeof(Oid) * indnkeyatts);
+	indexRelation->rd_exclstrats = (uint16 *) palloc(sizeof(uint16) * indnkeyatts);
+	memcpy(indexRelation->rd_exclops, ops, sizeof(Oid) * indnkeyatts);
+	memcpy(indexRelation->rd_exclprocs, funcs, sizeof(Oid) * indnkeyatts);
+	memcpy(indexRelation->rd_exclstrats, strats, sizeof(uint16) * indnkeyatts);
 	MemoryContextSwitchTo(oldcxt);
 }