Simplify code in objectaddress.c for some property graph objects

Property graph element labels and label properties relied on a direct
systable scan when retrieving their object descriptions.  These can be
simplified with get_catalog_object_by_oid().  This offers the benefit to
do a direct syscache lookup, if available.

The same logic will be used in a follow-up patch when retrieving the
object identity parts, applying the same rule across the board for these
object types.

Extracted from a larger patch by the author.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Alex Guo <guo.alex.hengchen@gmail.com>
Discussion: https://postgr.es/m/aej1DkLwhyZWmtxJ@bdtpg

diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c
index c186280957781ede3ce560d95303b512ab1c12ea..050b7829eb0ad2fb44d84165522a94f9655f1efe 100644 (file)
--- a/src/backend/catalog/objectaddress.c
+++ b/src/backend/catalog/objectaddress.c
@@ -4106,26 +4106,19 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
                case PropgraphElementLabelRelationId:
                        {
                                Relation        rel;
-                               SysScanDesc scan;
-                               ScanKeyData key[1];
                                HeapTuple       tuple;
                                Form_pg_propgraph_element_label pgelform;
                                ObjectAddress oa;
 
                                rel = table_open(PropgraphElementLabelRelationId, AccessShareLock);
-                               ScanKeyInit(&key[0],
-                                                       Anum_pg_propgraph_element_label_oid,
-                                                       BTEqualStrategyNumber, F_OIDEQ,
-                                                       ObjectIdGetDatum(object->objectId));
-
-                               scan = systable_beginscan(rel, PropgraphElementLabelObjectIndexId, true, NULL, 1, key);
-                               tuple = systable_getnext(scan);
+                               tuple = get_catalog_object_by_oid(rel,
+                                                                                                 Anum_pg_propgraph_element_label_oid,
+                                                                                                 object->objectId);
                                if (!HeapTupleIsValid(tuple))
                                {
                                        if (!missing_ok)
                                                elog(ERROR, "could not find tuple for element label %u", object->objectId);
 
-                                       systable_endscan(scan);
                                        table_close(rel, AccessShareLock);
                                        break;
                                }
@@ -4136,7 +4129,6 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
                                ObjectAddressSet(oa, PropgraphElementRelationId, pgelform->pgelelid);
                                appendStringInfoString(&buffer, getObjectDescription(&oa, false));
 
-                               systable_endscan(scan);
                                table_close(rel, AccessShareLock);
                                break;
                        }
@@ -4166,26 +4158,19 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
                case PropgraphLabelPropertyRelationId:
                        {
                                Relation        rel;
-                               SysScanDesc scan;
-                               ScanKeyData key[1];
                                HeapTuple       tuple;
                                Form_pg_propgraph_label_property plpform;
                                ObjectAddress oa;
 
                                rel = table_open(PropgraphLabelPropertyRelationId, AccessShareLock);
-                               ScanKeyInit(&key[0],
-                                                       Anum_pg_propgraph_label_property_oid,
-                                                       BTEqualStrategyNumber, F_OIDEQ,
-                                                       ObjectIdGetDatum(object->objectId));
-
-                               scan = systable_beginscan(rel, PropgraphLabelPropertyObjectIndexId, true, NULL, 1, key);
-                               tuple = systable_getnext(scan);
+                               tuple = get_catalog_object_by_oid(rel,
+                                                                                                 Anum_pg_propgraph_label_property_oid,
+                                                                                                 object->objectId);
                                if (!HeapTupleIsValid(tuple))
                                {
                                        if (!missing_ok)
                                                elog(ERROR, "could not find tuple for label property %u", object->objectId);
 
-                                       systable_endscan(scan);
                                        table_close(rel, AccessShareLock);
                                        break;
                                }
@@ -4196,7 +4181,6 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
                                ObjectAddressSet(oa, PropgraphElementLabelRelationId, plpform->plpellabelid);
                                appendStringInfoString(&buffer, getObjectDescription(&oa, false));
 
-                               systable_endscan(scan);
                                table_close(rel, AccessShareLock);
                                break;
                        }