names := strings.Split(chk, ",")
			if len(names) > 1 && regEnLetterAndMidline.MatchString(names[0]) {
				checks[names[0]] = CheckConstraint{Name: names[0], Constraint: strings.Join(names[1:], ","), Field: field}
			} else {
				if names[0] == "" {
					chk = strings.Join(names[1:], ",")
				}
				name := schema.namer.CheckerName(schema.Table, field.DBName)
				checks[name] = CheckConstraint{Name: name, Constraint: chk, Field: field}
			}
		}

		default:
			results[idx] = "nil"
			vv := reflect.ValueOf(v)
			if vv.IsValid() && !vv.IsZero() {
				results[idx] = fmt.Sprint(reflect.Indirect(vv).Interface())
			}
		}
	}

	return strings.Join(results, "_")
}

func Contains(elems []string, elem string) bool {
	for _, e := range elems {
		if elem == e {
			return true
		}
	}
	return false
}

func AssertEqual(x, y interface{}) bool {

}

// ColumnName convert string to column name
func (ns NamingStrategy) ColumnName(table, column string) string {
	return ns.toDBName(column)
}

// JoinTableName convert string to join table name
func (ns NamingStrategy) JoinTableName(str string) string {
	if !ns.NoLowerCase && strings.ToLower(str) == str {
		return ns.TablePrefix + str
	}

	if ns.SingularTable {