return constraint, getTable(rel)
		}
	}

	if field := stmt.Schema.LookUpField(name); field != nil {
		for k := range checkConstraints {
			if checkConstraints[k].Field == field {
				v := checkConstraints[k]
				return &v, stmt.Table
			}
		}

		for k := range uniqueConstraints {
			if uniqueConstraints[k].Field == field {
				v := uniqueConstraints[k]

)

// reg match english letters and midline
var regEnLetterAndMidline = regexp.MustCompile(`^[\w-]+$`)

type CheckConstraint struct {
	Name       string
	Constraint string // length(phone) >= 10
	*Field
}

func (chk *CheckConstraint) GetName() string { return chk.Name }

func (chk *CheckConstraint) Build() (sql string, vars []interface{}) {