Re: Finding duplicated values

Kent Anderson wrote:
> I have a few tables that have duplicated values from an import from a 
> different database. I have two keys I tried to set as primary and got an 
> error
> ERROR:  could not create unique index
> DETAIL:  Table contains duplicated values.
>  
> Is there some join I can use to compare the hmhmkey, wmwmkey pairs 
> against the table to find duplicate values? Each pair key should be 
> unique but the old database was less than normalized.
>  
> I was trying to use the code below but it returned no rows.
>  
> SELECT hmhmkey, wmwmkey
> FROM   exceptions
> EXCEPT
> SELECT hmhmkey, wmwmkey
> FROM  exceptions;
>  
> Any suggestions?
>  
> Kent Anderson
> EZYield.com
> 407-629-0900
> www.ezyield.com <http://www.ezyield.com/>

Try http://archives.postgresql.org/pgsql-sql/1999-03/msg00239.php