func (db *DB) AutoMigrate(dst ...interface{}) error {
	return db.Migrator().AutoMigrate(dst...)
}

// ViewOption view option
type ViewOption struct {
	Replace     bool   // If true, exec `CREATE`. If false, exec `CREATE OR REPLACE`
	CheckOption string // optional. e.g. `WITH [ CASCADED | LOCAL ] CHECK OPTION`
	Query       *DB    // required subquery.
}

// ColumnType column type interface
type ColumnType interface {