Simplify IsIndexUsableForReplicaIdentityFull()

Take Relation as argument instead of IndexInfo.  Building the
IndexInfo is an unnecessary intermediate step here.

A future patch wants to get some information that is in the relcache
but not in IndexInfo, so this will also help there.

Discussion: https://www.postgresql.org/message-id/333d3886-b737-45c3-93f4-594c96bb405d@eisentraut.org

src/backend/replication/logical/relation.c

@@ -781,11 +781,9 @@ FindUsableIndexForReplicaIdentityFull(Relation localrel, AttrMap *attrmap)
 	{
 		bool		isUsableIdx;
 		Relation	idxRel;
-		IndexInfo  *idxInfo;
 
 		idxRel = index_open(idxoid, AccessShareLock);
-		idxInfo = BuildIndexInfo(idxRel);
-		isUsableIdx = IsIndexUsableForReplicaIdentityFull(idxInfo, attrmap);
+		isUsableIdx = IsIndexUsableForReplicaIdentityFull(idxRel, attrmap);
 		index_close(idxRel, AccessShareLock);
 
 		/* Return the first eligible index found */
@@ -832,22 +830,22 @@ FindUsableIndexForReplicaIdentityFull(Relation localrel, AttrMap *attrmap)
  * to sequential execution, which might not be a good idea in some cases.
  */
 bool
-IsIndexUsableForReplicaIdentityFull(IndexInfo *indexInfo, AttrMap *attrmap)
+IsIndexUsableForReplicaIdentityFull(Relation idxrel, AttrMap *attrmap)
 {
 	AttrNumber	keycol;
 
 	/* Ensure that the index access method has a valid equal strategy */
-	if (get_equal_strategy_number_for_am(indexInfo->ii_Am) == InvalidStrategy)
+	if (get_equal_strategy_number_for_am(idxrel->rd_rel->relam) == InvalidStrategy)
 		return false;
 
 	/* The index must not be a partial index */
-	if (indexInfo->ii_Predicate != NIL)
+	if (!heap_attisnull(idxrel->rd_indextuple, Anum_pg_index_indpred, NULL))
 		return false;
 
-	Assert(indexInfo->ii_NumIndexAttrs >= 1);
+	Assert(idxrel->rd_index->indnatts >= 1);
 
 	/* The leftmost index field must not be an expression */
-	keycol = indexInfo->ii_IndexAttrNumbers[0];
+	keycol = idxrel->rd_index->indkey.values[0];
 	if (!AttributeNumberIsValid(keycol))
 		return false;
 
@@ -865,7 +863,7 @@ IsIndexUsableForReplicaIdentityFull(IndexInfo *indexInfo, AttrMap *attrmap)
 		IndexAmRoutine *amroutine;
 
 		/* The given index access method must implement amgettuple. */
-		amroutine = GetIndexAmRoutineByAmId(indexInfo->ii_Am, false);
+		amroutine = GetIndexAmRoutineByAmId(idxrel->rd_rel->relam, false);
 		Assert(amroutine->amgettuple != NULL);
 	}
 #endif

src/backend/replication/logical/worker.c

@@ -2931,7 +2931,7 @@ FindReplTupleInLocalRel(ApplyExecutionData *edata, Relation localrel,
 		/* Index must be PK, RI, or usable for REPLICA IDENTITY FULL tables */
 		Assert(GetRelationIdentityOrPK(localrel) == localidxoid ||
 			   (remoterel->replident == REPLICA_IDENTITY_FULL &&
-				IsIndexUsableForReplicaIdentityFull(BuildIndexInfo(idxrel),
+				IsIndexUsableForReplicaIdentityFull(idxrel,
 													edata->targetRel->attrmap)));
 		index_close(idxrel, AccessShareLock);
 #endif

src/include/replication/logicalrelation.h

@@ -48,7 +48,7 @@ extern LogicalRepRelMapEntry *logicalrep_partition_open(LogicalRepRelMapEntry *r
 														Relation partrel, AttrMap *map);
 extern void logicalrep_rel_close(LogicalRepRelMapEntry *rel,
 								 LOCKMODE lockmode);
-extern bool IsIndexUsableForReplicaIdentityFull(IndexInfo *indexInfo, AttrMap *attrmap);
+extern bool IsIndexUsableForReplicaIdentityFull(Relation idxrel, AttrMap *attrmap);
 extern Oid	GetRelationIdentityOrPK(Relation rel);
 
 #endif							/* LOGICALRELATION_H */