if field.IgnoreMigration {
		return nil
	}

	// found, smart migrate
	fullDataType := strings.TrimSpace(strings.ToLower(m.DB.Migrator().FullDataTypeOf(field).SQL))
	realDataType := strings.ToLower(columnType.DatabaseTypeName())

	var (
		alterColumn bool
		isSameType  = fullDataType == realDataType
	)

	if !field.PrimaryKey {
		// check type
		if !strings.HasPrefix(fullDataType, realDataType) {

pkg database/sql/driver, type TxOptions struct, ReadOnly bool
pkg database/sql, func Named(string, interface{}) NamedArg
pkg database/sql, method (*ColumnType) DatabaseTypeName() string
pkg database/sql, method (*ColumnType) DecimalSize() (int64, int64, bool)
pkg database/sql, method (*ColumnType) Length() (int64, bool)
pkg database/sql, method (*ColumnType) Name() string