| Index > Memecode > Stupid MySQL Bug | |
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| Author/Date | Stupid MySQL Bug |
| fret 13/09/2005 2:29am | I noticed that all the threads we're being sorted against the date of the first post instead of the date of the last post. So I thought I'd go a fix it.
Turns out there is a pretty major bug in MySQL, where if you have some sql like: select ParentPost, MAX(Date) from forum_post where forumid=2 group by ParentPost order by date desc The "MAX" function evaluates just one record, instead of the whole group created by the "group by" part of the command. If I take out the "where forumid=2" it starts to work. But I have to filter the results in PHP code afterwards. Slower but non-buggy. |
| claytas 12/09/2006 12:24am | Maybe too late, I only now stumbled on your site.
I would say the bug is that it didn't just say 'error'. Either alias the the expression, or put the aggregate in the group by. I am not so familiar with MySQL, mainly other SQLs. select ParentPost, MAX(Date) as MAXDATE from forum_post where forumid=2 group by ParentPost order by MAXDATE desc select ParentPost, MAX(Date) from forum_post where forumid=2 group by ParentPost order by Max(Date) desc |
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