Re: Aggregate weirdness - Mailing list pgsql-performance

Martin Kjeldsen <martin@martinkjeldsen.dk> writes:
> CREATE OR REPLACE VIEW v_test_with_number AS
>         SELECT
>                 t.*,
>                 (SELECT SUM(number) FROM test_use WHERE test_id = t.id) as numbers
>         FROM test t;

This is a bad way to do it --- the sub-select isn't readily optimizable.
Try something like

 SELECT t.id, t.name, sum(test_use.number) AS numbers
   FROM test_use
   JOIN test t ON test_use.test_id = t.id
  GROUP BY t.id, t.name;


            regards, tom lane