Randal L. Schwartz wrote:
I'm probably asking a FAQ, but a few google searches didn't seem to point me in the right place.
Is there a simple way with PostgreSQL to assign relative ranks to the result of a query ORDER BY? That is, I want to either have a view that cheaply assigns the ranks, or be able to update a column with the current ranks (yes, I know this latter version is more prone to error).
I'm certain there's probably something I can do to laminate an array value to a query result. Am I confused? (Yes!)
Randal,
May be you can use something like this:
create sequence seq_tmp;
select nextval('seq_tmp') as rank, a.id, a.name from (select id, name from t order by name desc) a;
drop sequence seq_tmp;
I don't know how cheap will this be (because of the sequence), but couldn't find another way. I do not think that we have something like Oracle's ROWNUM...
Regards, Lyubomir Petrov
P.S. I'm sure you can wrap it in plperl stored procedure :)
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