Re: how to remove the duplicate records from a table

Yi Zhao wrote:
> I have a table contains some duplicate records, and this table create
> without oids, for example:
> id | temp_id
> ----+---------
> 10 | 1
> 10 | 1
> 10 | 1
> 20 | 4
> 20 | 4
> 30 | 5
> 30 | 5
> I want get the duplicated records removed and only one is reserved, so
> the results is:
> 10 1
> 20 4
> 30 5
>
> I know create a temp table will resolve this problem, but I don't want
> this way:)
>
> can someone tell me a simple methold?

Don't know if you'd call that simple, but if the table is
called "t", you could do

DELETE FROM t t1 USING t t2
WHERE t1.id = t2.id AND t1.temp_id = t2.temp_id AND t1.ctid > t2.ctid;

Yours,
Laurenz Albe