diff --git a/contrib/dolphin/expected/keyword_ignore_test/ignore_type_transform.out b/contrib/dolphin/expected/keyword_ignore_test/ignore_type_transform.out
index 63ac0e8caaa10837c92d99e67cc9fdc76c21ac30..fa5751c3b0ae7ba08f64ef0436c5a9f8f7ae087b 100644
--- a/contrib/dolphin/expected/keyword_ignore_test/ignore_type_transform.out
+++ b/contrib/dolphin/expected/keyword_ignore_test/ignore_type_transform.out
@@ -789,8 +789,36 @@ select * from t_nvarchar2;
  123456789123456789
 (3 rows)
 
+-- test typecast with foreign key
+drop table if exists t1;
+NOTICE:  table "t1" does not exist, skipping
+create table t1(
+    column1 int ,
+    column2 char(10) primary Key,
+    column3 int,
+    unique(column1)
+);
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "t1_pkey" for table "t1"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "t1_column1_key" for table "t1"
+insert into t1 values(1,'df',22.22);
+insert into t1 values(2,'df1',22.22);
+insert into t1 values(3,'df2',22.22);
+drop table if exists t2;
+NOTICE:  table "t2" does not exist, skipping
+create table t2(
+    column1 int unique,
+    column2 char(10) primary Key
+);
+NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "t2_pkey" for table "t2"
+NOTICE:  CREATE TABLE / UNIQUE will create implicit index "t2_column1_key" for table "t2"
+insert into t2 values(1,'df');
+insert into t2 values(2,'dfd');
+insert into t2 values(3,'sdf');
+alter table t2 add foreign Key (column1) references t1(column2);
+ERROR:  insert or update on table "t2" violates foreign key constraint "t2_column1_fkey"
+DETAIL:  Key (column1)=(1) is not present in table "t1".
 drop schema sql_ignore_type_transform_test cascade;
-NOTICE:  drop cascades to 14 other objects
+NOTICE:  drop cascades to 16 other objects
 DETAIL:  drop cascades to table t
 drop cascades to table t_tinyint
 drop cascades to table t_smallint
@@ -805,4 +833,6 @@ drop cascades to table t_character
 drop cascades to table t_varchar2
 drop cascades to table t_nvarchar2
 drop cascades to table t_text
+drop cascades to table t1
+drop cascades to table t2
 reset current_schema;
diff --git a/contrib/dolphin/plugin_parser/gram.y b/contrib/dolphin/plugin_parser/gram.y
index 30ba6a7fa8190c8c8b98dd9772a9f546a7ebdfcb..2b26c4c9534eeb49ea41e4e49f024f3360dc2afe 100644
--- a/contrib/dolphin/plugin_parser/gram.y
+++ b/contrib/dolphin/plugin_parser/gram.y
@@ -45945,6 +45945,9 @@ static inline void ChangeBpcharCastType(TypeName* typname)
 		 * so I try to use location to distinguish the '(1)' is added by user or gram.y. since the location of
 		 * '(1)' added by gram.y is always -1.
 		*/
+		if (typname->typmods == NIL) {
+			return;
+		}
 		A_Const* typmods = (A_Const*)lfirst(list_head(typname->typmods));
 		if (typmods->val.val.ival == 1 && typmods->location == -1) {
 			list_free_deep(typname->typmods);
diff --git a/contrib/dolphin/sql/keyword_ignore_test/ignore_type_transform.sql b/contrib/dolphin/sql/keyword_ignore_test/ignore_type_transform.sql
index 468988ae0b8840739eadd2b07db52f1ac91b4caa..9a4fa6c8afd4af2eaac48544626b2817f596539a 100644
--- a/contrib/dolphin/sql/keyword_ignore_test/ignore_type_transform.sql
+++ b/contrib/dolphin/sql/keyword_ignore_test/ignore_type_transform.sql
@@ -344,5 +344,28 @@ insert into t_text values(123456789123456789);
 insert ignore into t_nvarchar2 select cont from t_text;
 select * from t_nvarchar2;
 
+-- test typecast with foreign key
+drop table if exists t1;
+create table t1(
+    column1 int ,
+    column2 char(10) primary Key,
+    column3 int,
+    unique(column1)
+);
+insert into t1 values(1,'df',22.22);
+insert into t1 values(2,'df1',22.22);
+insert into t1 values(3,'df2',22.22);
+
+drop table if exists t2;
+create table t2(
+    column1 int unique,
+    column2 char(10) primary Key
+);
+insert into t2 values(1,'df');
+insert into t2 values(2,'dfd');
+insert into t2 values(3,'sdf');
+
+alter table t2 add foreign Key (column1) references t1(column2);
+
 drop schema sql_ignore_type_transform_test cascade;
 reset current_schema;