select dup_columns,count((*)
from table
group by dup_columns
having count(*) > 1
On Monday 23 September 2002 11:46 pm, Andy Kriger wrote:
> I have a file of legacy data that has duplicate entries in a column that
> I'd like to have a unique index on. How can I query to find the duplicates
> (so I can determine if they can be thrown out)?
>
> thx
>
>
>
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