tidb: Limit and Offset not work

Please answer these questions before submitting your issue. Thanks!

1. What did you do? If possible, provide a recipe for reproducing the error.

using go mysql driver github.com/go-sql-driver/mysql

sql: select id from x LIMIT 10 OFFSET 5

or

sql: select id from x LIMIT 5,10

1. What did you expect to see?

10 results returns

1. What did you see instead?

15 results returns (But I run that command in mysql client, it works. Did I missing something?)

1. What version of Go are you using (go version)?

go 1.7.4