You would use some of postgresql built in date functions to extract the week from the date and group
by that
i.e.
select carrier, extract(week from start_time) as week, sum(call_length) as totallength, sum(cost) as
total_cost
from mytable
group by carrier, extract(week from start_time)
order by week, carrier
you'll probably want to extract the year as well so dates weeks from alternate years don't get
merged together
Ketema Harris wrote:
> I have a table defined as
>
> CREATE TABLE mytable
> (
> carrier varchar,
> start_time timestamp with time zone,
> call_date date,
> cost numeric,
> call_length numeric
> )
>
> I want to create a query that will generate a the following columns:
>
> carrier, week, sum(call_length) as totallength, sum(cost) as total_cost
> from mytable
> group by carrier, (WHAT HERE?)
> order by week, carrier
>
>
> week is defined as a date range so something like 7/6/2009 - 7/13/2009
>
> I would need the timestamps to be grouped into 7 day intervals starting
> from the first one and moving through the table. is this possible in a
> single query or would I have to write a function ?
>
>
