cr_histogram.sql
Save this script as cr_histogram.sql.
-- "scale_factor" controls the histogram height.
-- Use 10 for 10,000 rows, 100 for 100,000 rows.
create or replace function histogram(
no_of_bukets in int,
scale_factor in numeric)
returns SETOF text
language sql
as $body$
with
bucket_assignments as (
select bucket(dp_score, 0::double precision, 100::double precision, no_of_bukets) as bucket
from t4)
select
to_char(count(*), '9999')||' | '||
rpad('=', (count(*)/scale_factor)::int, '=')
from bucket_assignments
group by bucket
order by bucket;
$body$;