Re: [SQL] Group By Dilemma

"Tim Perdue" wrote:
>Hello, I am trying to do a GROUP BY so that I can get a count of messages
>with the same subject. The problem is, the optimizer won't let me group by
>just one column, when I am selecting several columns.

You can only have the grouped column and aggregates in your query.

>I suppose Postgres doesn't know which rows to leave out and which ones to
>display, but I'm hoping someone can offer a solution....
>
>SELECT
>fld_mailid,
>fld_mail_date,
>fld_mail_is_followup,
>fld_mail_from,
>fld_mail_subject, <-- Group only on this, so I can get a count
>count(*)
>FROM tbl_mail_archive
>WHERE fld_mail_list=1 AND
>fld_mail_year=1999 AND
>fld_mail_month=06
>group by fld_mail_subject
>ORDER BY fld_mail_date DESC
>LIMIT 26 OFFSET 0;

What do you expect to see in the other columns? Why are you including
them at all?

--
Oliver Elphick Oliver(dot)Elphick(at)lfix(dot)co(dot)uk
Isle of Wight http://www.lfix.co.uk/oliver
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