diff --git a/cdc/sink/mysql_test.go b/cdc/sink/mysql_test.go
index b7dbe1e49f0..a6669c5887a 100644
--- a/cdc/sink/mysql_test.go
+++ b/cdc/sink/mysql_test.go
@@ -444,13 +444,26 @@ func mockTestDB() (*sql.DB, error) {
 	return db, nil
 }
 
+func mockDBWithAdjustedSQLMode() (*sql.DB, sqlmock.Sqlmock, error) {
+	db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+	if err != nil {
+		return db, mock, err
+	}
+	// sql mode is adjust for compatibility.
+	mock.ExpectQuery("SELECT @@SESSION.sql_mode;").
+		WillReturnRows(sqlmock.NewRows([]string{"@@SESSION.sql_mode"}).
+			AddRow("STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE"))
+	mock.ExpectExec("SET sql_mode = 'ALLOW_INVALID_DATES,IGNORE_SPACE,NO_AUTO_VALUE_ON_ZERO';").
+		WillReturnResult(sqlmock.NewResult(0, 0))
+	return db, mock, err
+}
+
 func TestAdjustSQLMode(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
 	dbIndex := 0
 	mockGetDBConn := func(ctx context.Context, dsnStr string) (*sql.DB, error) {
-		fmt.Printf("mockGetDBConn is called\n")
 		defer func() {
 			dbIndex++
 		}()
@@ -461,16 +474,9 @@ func TestAdjustSQLMode(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 
-		// sql mode is adjust for compatibility.
-		mock.ExpectQuery("SELECT @@SESSION.sql_mode;").
-			WillReturnRows(sqlmock.NewRows([]string{"@@SESSION.sql_mode"}).
-				AddRow("STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE"))
-		mock.ExpectExec("SET sql_mode = 'ALLOW_INVALID_DATES,IGNORE_SPACE,NO_AUTO_VALUE_ON_ZERO';").
-			WillReturnResult(sqlmock.NewResult(0, 0))
-
 		// sql mode is adjust for compatibility.
 		mock.ExpectQuery("SELECT @@SESSION.sql_mode;").
 			WillReturnRows(sqlmock.NewRows([]string{"@@SESSION.sql_mode"}).
@@ -587,7 +593,7 @@ func TestNewMySQLSinkExecDML(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 		mock.ExpectBegin()
 		mock.ExpectExec("REPLACE INTO `s1`.`t1`(`a`,`b`) VALUES (?,?),(?,?)").
@@ -731,7 +737,7 @@ func TestExecDMLRollbackErrDatabaseNotExists(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 		mock.ExpectBegin()
 		mock.ExpectExec("REPLACE INTO `s1`.`t1`(`a`) VALUES (?),(?)").
@@ -797,7 +803,7 @@ func TestExecDMLRollbackErrTableNotExists(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 		mock.ExpectBegin()
 		mock.ExpectExec("REPLACE INTO `s1`.`t1`(`a`) VALUES (?),(?)").
@@ -863,7 +869,7 @@ func TestExecDMLRollbackErrRetryable(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 		for i := 0; i < defaultDMLMaxRetryTime; i++ {
 			mock.ExpectBegin()
@@ -912,7 +918,7 @@ func TestNewMySQLSinkExecDDL(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
 		require.Nil(t, err)
 		mock.ExpectBegin()
 		mock.ExpectExec("USE `test`;").WillReturnResult(sqlmock.NewResult(1, 1))
@@ -1042,7 +1048,8 @@ func TestNewMySQLSink(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
+		require.Nil(t, err)
 		mock.ExpectClose()
 		require.Nil(t, err)
 		return db, nil
@@ -1081,7 +1088,8 @@ func TestMySQLSinkClose(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
+		require.Nil(t, err)
 		mock.ExpectClose()
 		require.Nil(t, err)
 		return db, nil
@@ -1121,7 +1129,8 @@ func TestMySQLSinkFlushResovledTs(t *testing.T) {
 			return db, nil
 		}
 		// normal db
-		db, mock, err := sqlmock.New(sqlmock.QueryMatcherOption(sqlmock.QueryMatcherEqual))
+		db, mock, err := mockDBWithAdjustedSQLMode()
+		require.Nil(t, err)
 		mock.ExpectBegin()
 		mock.ExpectExec("REPLACE INTO `s1`.`t1`(`a`) VALUES (?)").
 			WithArgs(1).