retrieve rows where one field is duplicated

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#653

From: RB Smissaert
Date: Tue, 23 Oct 2007 21:18

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What would be the quickest way to retrieve all the rows
from a table where one field has duplicates in another row? So for example 
if we want the rows where f1 has
duplicates and the following table:

f1    f2
--------
A    1
A    2
B    3
C    4
C    5

retrieve all the rows except the one with B and 3.
I can do it with a subquery and group by and count > 1
but it is very slow.
I am coming to think that this may be best done in code
rather than in SQL, but maybe knows a way.

RBS

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From: "RB Smissaert" <bartsmissaert@blueyonder.co.uk>
Newsgroups: borland.public.interbase.sql
Subject: retrieve rows where one field is duplicated
Date: Tue, 23 Oct 2007 22:18:41 +0100
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