Merlin Moncure <[email protected]> writes:
> On Thu, Apr 16, 2009 at 2:02 AM, Lists <[email protected]> wrote:
>> select comment_date
>> from user_comments
>> where user_comments.uid=1
>> order by comment_date desc limit 1
> try this:
> create index comment_data_uid_idx on user_comments(uid, comment_date);
> select * from user_comments where (uid, comment_date) < (1, high_date)
> order by uid desc, comment_date desc limit 1;
You don't really need to complicate your queries like that. Having the
two-column index will suffice to make the given query work fine, at
least in reasonably modern PG versions (since 8.1 I think).
regards, tom lane
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