CREATE AGGREGATE array_accum(text) (
    SFUNC = array_append,
    STYPE = text[],
    INITCOND = '{}'
);
 
SELECT s_date,array_to_string(array_accum(h::text),'/'), 
   array_to_string(array_accum(co::text),'/')
FROM
(SELECT s_date,EXTRACT(hour FROM s_time) AS h,
   count(*) AS co
FROM foo f
GROUP BY s_date,h
ORDER BY s_date,h) t
GROUP BY s_date

SELECT * FROM crosstab(
'select s_date, EXTRACT(hour from u.s_time) as h, count(*) as co
from userw u
group by s_date,h
order by s_date,h',
'select h from generate_series(0,23) h')
AS (s_date date,h0 int,
h1 int,h2 int,h3 int,h4 int,h5 int,h6 int,
h7 int,h8 int,h9 int,h10 int,h11 int,h12 int,
h13 int,h14 int,h15 int,h16 int,h17 int,h18 int,
h19 int,h20 int,h21 int,h22 int,h23 int)