Imports github.com/pingcap/tidb/util/charset github.com/pingcap/tidb/util/hack github.com/juju/errors github.com/pingcap/tidb/ast github.com/pingcap/tidb/mysql github.com/pingcap/tidb/terror github.com/pingcap/tidb/util/types Standard library imports unicode bytes fmt math regexp strconv strings unicode/utf8