Re: contracting tables

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От Markus Bertheau
Тема Re: contracting tables
Дата
Msg-id 1007106809.1107.11.camel@entwicklung01.cenes.de
обсуждение исходный текст
Ответ на contracting tables  ("Peter T. Brown" <peter@memeticsystems.com>)
Ответы Re: contracting tables  ("Christopher Kings-Lynne" <chriskl@familyhealth.com.au>)
Список pgsql-sql
On Fri, 2001-11-30 at 00:50, Peter T. Brown wrote:
> I have a table with many records, some of which are duplicates (there is no
> unique constraints). How can I contract this table to remove any of these
> duplicate records? Like when using GROUP BY in a select statement, except
> that I want to just remove the extra entries from this table directly... Any
> ideas?

If I understood you right, one problem is to identify only one row of a
duplicate. There is a 'hidden' field oid in every table that is unique.
It goes like this:

select oid, * from <yourtable>

So you could delete the rows by oid:

delete from <yourtable> where oid = <oid>

HTH

Markus Bertheau



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