[Resolved] LIMIT problem

rob76

I'm trying to delete specific rows from a table in mysql but find that if I specify a starting point, the query won't work.

Eg. this doesn't work:

DELETE FROM click_log WHERE id='$id' LIMIT 50, 60

but this does:

DELETE FROM click_log WHERE id='$id' LIMIT 60

Again, this works:

DELETE FROM click_log WHERE id='$id' LIMIT 10

But this doesn't:

DELETE FROM click_log WHERE id='$id' LIMIT 0, 10

Any help or explanation would be appreciated.

Thanks
Rob

drawmack

http://dev.mysql.com/doc/mysql/en/DELETE.html

With the DELETE function the LIMIT function provides for only a single number which is the row count.

rob76

Thanks for that. I have an application where I want to delete the first (say 10 rows) of a result set. However I find that this deletes the last 10 rows.

DELETE FROM click_log WHERE id='$id' LIMIT 10

How do I turn it round so it deletes the first 10 rows?

drawmack

Dude I posted a link to the manual entry on delete, did you try reading that?

rob76

Yes, sorry about that

I had actually tried this before (as per the manual), but again for some reason when I try to change the order this way nothing gets deleted.

DELETE FROM click_log WHERE id='$id' ORDER by count DESC LIMIT 10

Thanks

tsinka

Hi,

ORDER BY can be used with DELETE queries as of MySQL 4.0.0. This will not work with MySQL 3.x.

In that case you might have to execute a select statement to fetch the ids and then execute a DELETE query with that ids.

Thomas

rob76

Thanks for the info. I've started a new thread on this which explains more fully what I'm trying to achieve.