On Jun 18, 2007, at 10:17 , Michael Glaesemann wrote:
Looking over your function, I'm a little confused about what you're
trying to do. I'm guessing the (final) result you're trying to get
is the number of hours lost for each product per area per month for
the three years prior to the provided date.
Or, rather, the number of hours lost per production area per month
for the three years prior to the provided date.
SELECT date_trunc('month', production.production_date)::date
AS production_period
, product.id_production_area
, sum(production_hours) as total_production_hours
FROM production
JOIN product USING (id_product)
WHERE lost_hours = 'S'
AND date_trunc('month', a.production_date)::date BETWEEN
date_trunc('month', ? - 3 * interval '1 year')::date
AND date_trunc('month', ?)::date;
Looks like I forgot the GROUP BY clause:
GROUP BY production_period, id_production_area
Michael Glaesemann
grzm seespotcode net
