Re: [SQL] Group By Dilemma

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От Oliver Elphick
Тема Re: [SQL] Group By Dilemma
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Msg-id 199906040741.IAA04924@linda.lfix.co.uk
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Ответ на Group By Dilemma  ("Tim Perdue" <perdue@raccoon.com>)
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"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.
Theproblem 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
asolution.... > >SELECT >fld_mailid, >fld_mail_date, >fld_mail_is_followup, >fld_mail_from, >fld_mail_subject,   <--
Grouponly 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.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver              PGP key from public servers; key
ID32B8FAA1                ========================================    "But without faith it is impossible to please
him;for      he that cometh to God must believe that he is, and      that he is a rewarder of them that diligently seek
    him."       Hebrews 11:6 
 




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