Basically I have mytable in Postgresql which is defined
id integer,
ownername text,
length integer,
status integer
Intended outcome is to create a view that will have the following columns for each ownername row
ownername | count_in_status1 | sum_length_status1 | count_in_status2 | sum_length_status2 | count_in_status3 | sum_length_status3 | ..... | total_count | total_sum_length
It's a bit hard to explain but basically I need a count and sum per ownername with a total count and total sum of length at the end. At the moment there are actually 5 statuses
Tried the below
create view myview as
select ownername, status, count(*), sum(length) from mytable group by ownername, status
This returns the data but not in the most efficient manner that I presented above. How to achieve it?
I think this is what you want:
create view myview as
select ownername,
count(*) filter (where status = 1) as cnt_status_1,
sum(length) filter (where status = 1) as len_status_1,
count(*) filter (where status = 2) as cnt_status_2,
sum(length) filter (where status = 2) as len_status_2,
. . . -- continue for each status
count(*) as cnt,
sum(length) as length
from mytable
group by ownername;
Using Filter
is an elegant solution (see @Gordon Linoff response)
Te be more compatible with many database, yan can also write :
create view myview as
select ownername,
sum(case when status = 1 then 1 else 0 end) as cnt_status_1,
sum(case when status = 1 then length else 0 end) as len_status_1,
sum(case when status = 1 then 1 else 0 end) as cnt_status_2,
sum(case when status = 1 then length else 0 end) as len_status_2,
. . . -- continue for each status
count(*) as cnt,
sum(length) as length
from mytable
group by ownername;
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