Re: Adding PRIMARY KEY: Table contains duplicated values

On 02/04/2013 06:45 AM, Alexander Farber wrote:
> Trying to delete the older of the duplicated pairs:
>
> # SELECT id, author, count(1), max(stamp) as maxx
> FROM pref_rep
> GROUP BY id, author
> HAVING count(1) >1 and stamp < maxx;
> ERROR: column "maxx" does not exist
> LINE 4: HAVING count(1) >1 and stamp < maxx;
> ^

Caffeine has not reached critical mass yet, so test before using:

SELECT * FROM pref_rep JOIN (SELECT id, author, count(1) AS ct,
max(stamp) AS maxx FROM pref_rep GROUP BY id,author) max_time ON
max_time.id=pref_rep.id WHERE ct > 1 AND stamp < maxx;
>

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com