On 5 Mar 2010, at 11:28, John777 wrote: > Hi, > > Here are sample stat: > - Template_product has 1,033040 rows > - template_all_in_one has 93,796,400 rows > > I basically need to calculate the total for each article in > template_all_in_one and update it to Template_product. > > What is the best way to improve the performance? I already have 7 > indexes specify for the column. My desktop has 4quad and 8 GB memory. > it only used up 1 GB memory. is it possible to increase the memory, so > the query will use more memory and end up faster performance? > > =================================== > CREATE OR REPLACE FUNCTION test_update_template_db() > RETURNS integer AS > $BODY$ > DECLARE > text_manipulation TEXT :=''; > row_data template_product%ROWTYPE; > > BEGIN > > FOR row_data IN SELECT * FROM template_product LOOP > > update template_product set total_all_in_one = (select count(*) > from template_all_in_one where template_article_name = > row_data.template_article_name) > where template_product.id = row_data.id; > > END LOOP; > > RETURN 1; > END; > $BODY$ > LANGUAGE 'plpgsql' VOLATILE > COST 100; > ALTER FUNCTION test_update_template_db() OWNER TO postgres; > ======================================== I'd say drop the stored procedure and use SQL, something like: UPDATE template_product SET total_all_in_one = p.total FROM ( SELECT template_article_name, COUNT(*) AS total FROM template_product GROUP BY template_article_name ) AS p WHERE template_product.template_article_name = p.template_article_name; Alban Hertroys -- If you can't see the forest for the trees, cut the trees and you'll see there is no forest. !DSPAM:737,4b91809f296922908710608! -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
