Try
SELECT *
FROM mytable
WHERE (identification_number,date_of_birth) IN
(SELECT identification_number
, date_of_birth
FROM mytable m2
GROUP BY identification_number,data_of_birth
HAVING COUNT(*) > 1
)
There are other ways of doing it, perhaps more efficient.
Vincent
> I've look for a solution to this, but have only been able to find
> solutions to delete duplicate entries in a table by deleting entries not
> returned by SELECT DISTINCT.
>
> What sql should I use to SELECT entries in a table that have two
> particular column values that match?
>
> For example, my_table has
> name, phone number, identification_number, zip code, date of birth, and
> city
>
> I want to SELECT rows from this table that have the same values in
> identification and date of birth (duplicates) so I can have the user
> look at them in order to figure out which one to delete.
>
> I tried something like:
>
> $db_sql = "SELECT * FROM my_table GROUP BY identification_number
> HAVING count(date_of_birth) > 1 ORDER BY name"
>
> but that doesn't seem to work.
>
> Thanks,
> Bruce
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: Have you searched our list archives?
>
> http://archives.postgresql.org
>
---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match
