Add SysCacheGetAttrNotNull for guaranteed not-null attrs

When extracting an attr from a cached tuple in the syscache with
SysCacheGetAttr the isnull parameter must be checked in case the
attr cannot be NULL.  For cases when this is known beforehand, a
wrapper is introduced which perform the errorhandling internally
on behalf of the caller, invoking an elog in case of a NULL attr.

Reviewed-by: Tom Lane <[email protected]>
Reviewed-by: Peter Eisentraut <[email protected]>
Reviewed-by: David Rowley <[email protected]>
Discussion: https://postgr.es/m/[email protected]

1 files changed, 4 insertions, 6 deletions

diff --git a/src/backend/utils/cache/partcache.c b/src/backend/utils/cache/partcache.c
index 4f53d472333..5f3516ad0c2 100644
--- a/src/backend/utils/cache/partcache.c
+++ b/src/backend/utils/cache/partcache.c
@@ -130,15 +130,13 @@ RelationBuildPartitionKey(Relation relation)
 
 	/* But use the hard way to retrieve further variable-length attributes */
 	/* Operator class */
-	datum = SysCacheGetAttr(PARTRELID, tuple,
-							Anum_pg_partitioned_table_partclass, &isnull);
-	Assert(!isnull);
+	datum = SysCacheGetAttrNotNull(PARTRELID, tuple,
+								   Anum_pg_partitioned_table_partclass);
 	opclass = (oidvector *) DatumGetPointer(datum);
 
 	/* Collation */
-	datum = SysCacheGetAttr(PARTRELID, tuple,
-							Anum_pg_partitioned_table_partcollation, &isnull);
-	Assert(!isnull);
+	datum = SysCacheGetAttrNotNull(PARTRELID, tuple,
+								   Anum_pg_partitioned_table_partcollation);
 	collation = (oidvector *) DatumGetPointer(datum);
 
 	/* Expressions */