I'm trying to get this query to work: update sectors set companies =(select companies from industries where sector_id =sectors.id); PG returns: ERROR: more than one row returned by a subquery used as an expression Column companies is just a count of rows in the related companies table. Queries like this worked: update industries set companies =(select count(id) from companies where industry_id =industries.id); I know I could do a join in the subselect, but I'm curious why this doesn't work. If I do the subselect by itself, it looks like all of the rows from the industries table are return (I expected an error). Is this the "implicit FROM" gotcha? CSN __________________________________ Yahoo! Music Unlimited Access over 1 million songs. Try it free. http://music.yahoo.com/unlimited/ ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org