func RegisterSerializer(name string, serializer SerializerInterface) {
	serializerMap.Store(strings.ToLower(name), serializer)
}

// GetSerializer get serializer
func GetSerializer(name string) (serializer SerializerInterface, ok bool) {
	v, ok := serializerMap.Load(strings.ToLower(name))
	if ok {
		serializer, ok = v.(SerializerInterface)
	}
	return serializer, ok
}

func init() {
	RegisterSerializer("json", JSONSerializer{})

	NamedPet  *Pet
	Toys      []Toy   `gorm:"polymorphic:Owner"`
	Tools     []Tools `gorm:"polymorphicType:Type;polymorphicId:CustomID"`
	CompanyID *int
	Company   Company
	ManagerID *uint
	Manager   *User
	Team      []User     `gorm:"foreignkey:ManagerID"`
	Languages []Language `gorm:"many2many:UserSpeak;"`
	Friends   []*User    `gorm:"many2many:user_friends;"`
	Active    bool
}

type Account struct {
	gorm.Model

}

// PrimaryKey returns the index is primary key or not.
func (idx Index) PrimaryKey() (isPrimaryKey bool, ok bool) {
	return idx.PrimaryKeyValue.Bool, idx.PrimaryKeyValue.Valid
}

// Unique returns whether the index is unique or not.
func (idx Index) Unique() (unique bool, ok bool) {
	return idx.UniqueValue.Bool, idx.UniqueValue.Valid
}

// Option return the optional attribute of the index
func (idx Index) Option() string {

		}
	} else {
		onConflict.DoNothing = true
	}

	return
}

func saveAssociations(db *gorm.DB, rel *schema.Relationship, rValues reflect.Value, selectColumns map[string]bool, restricted bool, defaultUpdatingColumns []string) error {
	// stop save association loop
	if checkAssociationsSaved(db, rValues) {
		return nil
	}

	var (
		selects, omits []string

}

// Expr raw expression
type Expr struct {
	SQL                string
	Vars               []interface{}
	WithoutParentheses bool
}

// Build build raw expression
func (expr Expr) Build(builder Builder) {
	var (
		afterParenthesis bool
		idx              int
	)

	for _, v := range []byte(expr.SQL) {
		if v == '?' && len(expr.Vars) > idx {
			if afterParenthesis || expr.WithoutParentheses {

		}
	}

	return ""
}

func IsValidDBNameChar(c rune) bool {
	return !unicode.IsLetter(c) && !unicode.IsNumber(c) && c != '.' && c != '*' && c != '_' && c != '$' && c != '@'
}

// CheckTruth check string true or not
func CheckTruth(vals ...string) bool {
	for _, val := range vals {
		if val != "" && !strings.EqualFold(val, "false") {
			return true
		}
	}

func (m Migrator) ReorderModels(values []interface{}, autoAdd bool) (results []interface{}) {
	type Dependency struct {
		*gorm.Statement
		Depends []*schema.Schema
	}

	var (
		modelNames, orderedModelNames []string
		orderedModelNamesMap          = map[string]bool{}
		parsedSchemas                 = map[*schema.Schema]bool{}
		valuesMap                     = map[string]Dependency{}

	"strings"
	"time"
	"unicode"

	"gorm.io/gorm/utils"
)

const (
	tmFmtWithMS = "2006-01-02 15:04:05.999"
	tmFmtZero   = "0000-00-00 00:00:00"
	nullStr     = "NULL"
)

func isPrintable(s string) bool {
	for _, r := range s {
		if !unicode.IsPrint(r) {
			return false
		}
	}
	return true
}

// A list of Go types that should be converted to SQL primitives

	t.Run("CheckSchema/"+s.Name, func(t *testing.T) {
		tests.AssertObjEqual(t, s, v, "Name", "Table")

		for idx, field := range primaryFields {
			var found bool
			for _, f := range s.PrimaryFields {
				if f.Name == field {
					found = true
				}
			}

			if idx == 0 {
				if field != s.PrioritizedPrimaryField.Name {

}

var _ Namer = (*NamingStrategy)(nil)

// NamingStrategy tables, columns naming strategy
type NamingStrategy struct {
	TablePrefix         string
	SingularTable       bool
	NameReplacer        Replacer
	NoLowerCase         bool
	IdentifierMaxLength int
}

// TableName convert string to table name
func (ns NamingStrategy) TableName(str string) string {
	if ns.SingularTable {