From: Emi Lu <emilu@encs.concordia.ca>
To: Oliveiros d'Azevedo Cristina <oliveiros.cristina@marktest.pt>
Cc: pgsql-sql@postgresql.org
Subject: Re: how to get row number in select query
Date: Thu, 27 Jan 2011 09:32:09 -0500
Message-ID: <4D4181E9.2000305@encs.concordia.ca> (raw)
In-Reply-To: <D25246ED495942DD8E5777F5F9439DD0@marktestcr.marktest.pt>
References: <4D4047C1.5030208@encs.concordia.ca>
<D25246ED495942DD8E5777F5F9439DD0@marktestcr.marktest.pt>
Hi Oliveiros,
> If it is to order in ascendent fashion by, say, lname,
> one possibility would be
>
> SELECT COUNT(b.*) as row_number, a.lname,a.gname
> FROM "Table1" a, "Table2" b
> WHERE a.lname >= b.lname
> GROUP BY a.lname,a.gname
> ORDER BY row_number
>
> If you want to order by gname just change the WHERE clause accordingly
>
> N.B. : This works as long as there is no repetition on the column you
> use to order.
> If there is, we'll need a way to tie break. What is your specific case?
>
> Also, note that this method is time consuming, and would work only for
> relatively small tables.
> AFAIK, version 8.3 doesn't have any "non-standard SQL" way to get a row
> number, but it is possible that something like that has been introduced
> in later versions...
Thank you for the answer. I see psql8.4 has the method. I am not
interest in ordering any columns, but just a line num.
I'd like to get it from DB since displaytag _rowNum does not display row
num correctly: 1, 10, 11, 12.... 2, 3, 4, 5, 6...
Thanks,
--
Lu Ying
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To: pgsql-sql@postgresql.org
Cc: emilu@encs.concordia.ca, oliveiros.cristina@marktest.pt
Subject: Re: how to get row number in select query
In-Reply-To: <4D4181E9.2000305@encs.concordia.ca>
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