Can I simplify this somehow?

I tried(!) to write this as a with (CTE), but failed.

Can one of the CTE experts (or better SQL writer) help me here?

-- generate a table of timestamps to match against
select
generate_series(date_trunc('day',now()-'45 days'::interval),now()+'1
hour'::inte
rval,'1 hour')
    AS thetime  into temp table timestamps;

-- get a count of logged in users for a particular time
SELECT thetime,case extract(dow  from thetime)
                when 0 then 'Sunday'
                when 1 then 'Monday'
                when 2 then 'Tuesday'
                when 3 then 'Wednesday'
                when 4 then 'Thursday'
                when 5 then 'Friday'
                when 6 then 'Saturday' end AS "Day", count(*) AS
"#LoggedIn"
FROM  timestamps,user_session
WHERE thetime BETWEEN login_time AND COALESCE(logout_time, now())
GROUP BY thetime
ORDER BY thetime;

Thanks for any help at all.


--
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 214-642-9640 (c)     E-Mail: ler@lerctr.org
US Mail: 108 Turvey Cove, Hutto, TX 78634-5688