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From "John T. Dow" <j...@johntdow.com>
Subject Re: finding duplicates?
Date Sat, 14 Feb 2009 04:02:06 GMT
You might start with this:

select OtherKey, count(*) from Table group by OtherKey having count(*) > 1


On Fri, 13 Feb 2009 16:16:54 -0800, Kent Spaulding wrote:

>Hi all,
>
>I could use a little guidance for solving a tricky (to me, a noob) SQL  
>problem in Derby.
>
>I have a table with columns like:
>
>PrimaryKey, Enabled, OtherKey
>
>The 'OtherKey' values are supposed to be unique, but because we have  
>dirty data - they aren't.
>
>I want to construct a query to list OtherKey values that appear more  
>than once, and are enabled.
>
>So for data like:
>
>PrimaryKey,Enabled,OtherKey
>pk01,T,okNotADupe0
>pk02,T,okDupe
>pk03,T,okDupe
>pk04,F,okDupe
>pk05,T,okNotADupe1
>
>the query would return:
>
>DupedOtherKey,PrimaryKeys
>okDupe, "pk02|pk03"
>
>The PrimaryKeys column is a list of strings, separated by '|'.
>
>Is this easy to do in Derby?
>
>Thanks in advance,
>--Kent



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