diff --git a/src/common/backend/utils/adt/ruleutils.cpp b/src/common/backend/utils/adt/ruleutils.cpp
index 1b0849a39..d89abda5b 100644
--- a/src/common/backend/utils/adt/ruleutils.cpp
+++ b/src/common/backend/utils/adt/ruleutils.cpp
@@ -1641,7 +1641,7 @@ static int get_table_attribute(
                             find_nextval_seqoid_walker(adexpr, &tableinfo->autoinc_seqoid);
                             tableinfo->autoinc_attnum = attrdef->adnum;
                             appendStringInfo(buf, " %s", adsrc);
-                        } else {
+                        } else if (pg_strcasecmp(adsrc, "") != 0) {
                             appendStringInfo(buf, " DEFAULT %s", adsrc);
                         }
                         if (isOnUpdate) {
diff --git a/src/test/regress/expected/function_get_table_def.out b/src/test/regress/expected/function_get_table_def.out
index b9251e628..6cc37c473 100644
--- a/src/test/regress/expected/function_get_table_def.out
+++ b/src/test/regress/expected/function_get_table_def.out
@@ -788,7 +788,7 @@ select * from pg_get_tabledef('test');
  CREATE TABLE test (                                                         +
      a integer,                                                              +
      b timestamp without time zone DEFAULT now() ON UPDATE CURRENT_TIMESTAMP,+
-     c timestamp with time zone DEFAULT  ON UPDATE CURRENT_TIMESTAMP(5)      +
+     c timestamp with time zone ON UPDATE CURRENT_TIMESTAMP(5)               +
  )                                                                           +
  WITH (orientation=row, compression=no);
 (1 row)