}
}

func TestGaussDBAlterColumnDataType(t *testing.T) {
	if DB.Dialector.Name() != "gaussdb" {
		t.Skip()
	}
	DB.Migrator().DropTable(&Company{})
	DB.AutoMigrate(Company{})
	if err := DB.Table("companies").Migrator().AlterColumn(CompanyNew{}, "name"); err != nil {
		t.Fatalf("failed to alter column from string to int, got error %v", err)
	}

	DB.AutoMigrate(Company{})

	"sort"
	"time"

	"gorm.io/gorm/schema"
	"gorm.io/gorm/utils"
)

func initializeCallbacks(db *DB) *callbacks {
	return &callbacks{
		processors: map[string]*processor{
			"create": {db: db},
			"query":  {db: db},
			"update": {db: db},
			"delete": {db: db},
			"row":    {db: db},
			"raw":    {db: db},
		},
	}
}

// callbacks gorm callbacks manager
type callbacks struct {

			}
		}
	}

	results, err = db.Preload("Pets", func(db gorm.PreloadBuilder) error {
		db.Order("name").LimitPerRecord(5)
		return nil
	}).Preload("Friends", func(db gorm.PreloadBuilder) error {
		db.Order("name")
		return nil
	}).Where("name in ?", names).Find(ctx)

	for _, result := range results {

			dbDSN = sqlserverDSN
		}
		db, err = gorm.Open(sqlserver.Open(dbDSN), cfg)
	case "tidb":
		log.Println("testing tidb...")
		if dbDSN == "" {
			dbDSN = tidbDSN
		}
		db, err = gorm.Open(mysql.Open(dbDSN), cfg)
	default:
		log.Println("testing sqlite3...")
		db, err = gorm.Open(sqlite.Open(filepath.Join(os.TempDir(), "gorm.db")), cfg)
		if err == nil {
			db.Exec("PRAGMA foreign_keys = ON")
		}
	}

		}}

		if err := DB.Create(&pets).Error; err != nil {
			t.Fatalf("errors happened when create: %v", err)
		}

		for _, pet := range pets {
			CheckPet(t, *pet, *pet)
		}
	})
}

func TestCreateEmptyStruct(t *testing.T) {
	type EmptyStruct struct {
		ID uint
	}
	DB.Migrator().DropTable(&EmptyStruct{})

	if err := DB.AutoMigrate(&EmptyStruct{}); err != nil {

	}

	if err := DB.Create(&data).Error; err != nil {
		t.Fatalf("failed to create data, got error %v", err)
	}

	var result SerializerStruct
	if err := DB.Where("roles2 IS NULL AND roles3 = ?", "").First(&result, data.ID).Error; err != nil {
		t.Fatalf("failed to query data, got error %v", err)
	}

	AssertEqual(t, result, data)

	if err := DB.Model(&result).Update("roles", "").Error; err != nil {

			if errTranslator, ok := db.Dialector.(ErrorTranslator); ok {
				err = errTranslator.Translate(err)
			}
		}

		if db.Error == nil {
			db.Error = err
		} else {
			db.Error = fmt.Errorf("%v; %w", db.Error, err)
		}
	}
	return db.Error
}

// DB returns `*sql.DB`
func (db *DB) DB() (*sql.DB, error) {
	connPool := db.ConnPool
	if db.Statement != nil && db.Statement.ConnPool != nil {

func (db *DB) Commit() *DB {
	if committer, ok := db.Statement.ConnPool.(TxCommitter); ok && committer != nil && !reflect.ValueOf(committer).IsNil() {
		db.AddError(committer.Commit())
	} else {
		db.AddError(ErrInvalidTransaction)
	}
	return db
}

// Rollback rollbacks the changes in a transaction
func (db *DB) Rollback() *DB {

	// after model changed
	if DB.Statement.DryRun || DB.DryRun {
		t.Fatal("Failed expect DB.DryRun and DB.Statement.ToSQL to be false")
	}

	if DB.Statement.SQL.String() != "" {
		t.Fatal("Failed expect DB.Statement.SQL to be empty")
	}

	// first
	sql = DB.ToSQL(func(tx *gorm.DB) *gorm.DB {

	return c.with(func(db *DB) *DB {
		return db.Not(query, args...)
	})
}

func (c chainG[T]) Or(query interface{}, args ...interface{}) ChainInterface[T] {
	return c.with(func(db *DB) *DB {
		return db.Or(query, args...)
	})
}

func (c chainG[T]) Limit(offset int) ChainInterface[T] {
	return c.with(func(db *DB) *DB {
		return db.Limit(offset)
	})
}