AssertEqual(t, true, ok)

	//  empty string -> 123
	err = DB.Table("unique_tests").AutoMigrate(&UniqueTest4{})
	if err != nil {
		t.Fatalf("AutoMigrate err:%v", err)
	}

	ct, err = findColumnType(&UniqueTest{}, "name")
	if err != nil {
		t.Fatalf("findColumnType err:%v", err)
	}

	value, ok = ct.DefaultValue()
	AssertEqual(t, "123", value)
	AssertEqual(t, true, ok)

	//  123 -> null