Yes, large offsets could be a problem, we know this problem and we solved it with our customized JDBC driver, forbiding too large OFFSETs. However, a JDBC driver can not make OFFSETs faster.
And, if OFFSETs can be pushed down, the index can be built into a skip list, which is fast even with lists of millions of elements. On Sat, Mar 13, 2010 at 11:21 PM, MARK CALLAGHAN <[email protected]> wrote: > On Sat, Mar 13, 2010 at 12:59 AM, Yuan Wang <[email protected]> wrote: >> I think Drizzle should consider the ability to push down OFFSET to the >> storage engine. LIMIT/OFFSET is very common in most Web applications. >> Where there are lists, there are LIMIT/OFFSETs. For example, each user >> in Blog has a list of his articles. For this list could be long, we >> display it in pages, using the following SQL: > > This is a nice description of the problem and the feature that you > need. But I have been burned so many times in production by queries > with large offsets that I also want a feature to allow me to either > ban queries with an offset or set a limit on the max offset that can > be used. Of course, I can do that whether or not the optimization you > have requested is supported. > > Note that I don't write SQL, I just debug it and make it less slow and > this was written from experience -- > http://www.facebook.com/note.php?note_id=206034210932 > > -- > Mark Callaghan > [email protected] > _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
