Re: [SQL] Duplicate rows
Andy <alewis@mpsi.net>
From: Andy Lewis <alewis@mpsi.net>
To: phd2@earthling.net
Cc: pgsql-sql@postgreSQL.org
Date: 1998-05-16T14:10:06Z
Lists: pgsql-sql
Thanks, I'll give it a try. Andy On Sat, 16 May 1998, Oleg Broytmann wrote: >Hi! > >On Sat, 16 May 1998, Andy Lewis wrote: >> Right, I know that there are dups in the column. But, I don't know where they >> are nor do I know their value(s). I want to be able to find, say, two interger >> values that are in the same column but, different rows. > > It seems that you need a correlated subquery - a loop for every row, that >tests whether there are equal values. > >SELECT oid, mycolumn FROM mytable a > WHERE mycolumn IN > (SELECT oid, mycolumn FROM mytable b > WHERE a.oid <> b.oid) > >Or may be, join with the same table. Not sure what is better in this >situation. > >SELECT oid, mycolumn FROM mytable a, mytable b > WHERE a.oid <> b.oid AND > a.mycolumn = b.mycolumn > > In both cases "a.oid <> b.oid" excludes the same row from comparison (I >am pretty sure that in the same row a.mycolumn = b.column :). > >Oleg. >---- > Oleg Broytmann http://members..tripod.com/~phd2/ phd2@earthling.net > Programmers don't die, they just GOSUB without RETURN. > >