AssertEqual(t, false, ok)

	// null -> null
	err = DB.Table("unique_tests").AutoMigrate(&UniqueTest2{})
	if err != nil {
		t.Fatalf("AutoMigrate err:%v", err)
	}

	// not trigger alert column
	AssertEqual(t, true, DB.Migrator().HasConstraint(&UniqueTest{}, "uni_unique_tests_name"))
	AssertEqual(t, false, DB.Migrator().HasIndex(&UniqueTest{}, "name"))