hi there, something brainboggling :-) three tables: fac with: id | integer | not null default nextval('fac_id_seq'::text) pre with: id | integer | not null default nextval('pre_id_seq'::text) fac_id | integer | date | date | production | float8 | prd with: id | integer | not null default nextval('prd_id_seq'::text) date | date | fac_id | integer | prediction | float8 | the last two have constraints as foreign keys "fac_id int4 references fac (id)" pre has only one row per month prd has one value per day if i do a select count(fac.id) as fac_id, sum(prd.production) as prd_production, sum(pre.prediction) as pre_prediction from fac, pre, prd where date_part('year',timestamp(prd.date))=date_part('year',timestamp(pre.date)) and date_part('month',timestamp(prd.date))=date_part('month',timestamp(pre.date)) and pre.fac_id=fac.id and prd.fac_id=fac.id group by fac.id what i acctually want is a result that shows the summed production of a year and the summed prediction of a year at the same time i got values of 365 for fac_id before i had the constraints :-), which was perfectly well. now it shows 372 (like 31x12) if i keep it as is 4392 (like 365x12) if i ommit the month-where-clause. what's wrong can anybody help, this goes over my know-how :-) happy weekend and thanks for the great help lately from the list olaf -- soli-con Engineering Zanger, Dipl.-Ing. (FH) Olaf Marc Zanger Lorrainestrasse 23, 3013 Bern / Switzerland fon:+41-31-332 9782, mob:+41-76-572 9782 mailto:[EMAIL PROTECTED], http://www.soli-con.com