Thread: pivot query with count
The following is my code and results:
select '1' "num_ads",
(case when r.region_code = 1000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 1000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "NorthEast",
(case when r.region_code = 2000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 2000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "NorthWest",
(case when r.region_code = 3000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 3000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "SouthEast",
(case when r.region_code = 4000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 4000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "SouthWest",
(case when r.region_code = 5000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 5000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "Middle of Nowhere"
from user_region u, region r
where u.region_code = r.region_code
group by r.region_code;
num_ads | NorthEast | NorthWest | SouthEast | SouthWest | Middle of Nowhere
---------+-----------+-----------+-----------+-----------+-------------------
1 | 0 | 0 | 3898 | 0 | 0
1 | 3895 | 0 | 0 | 0 | 0
1 | 0 | 3873 | 0 | 0 | 0
1 | 0 | 0 | 0 | 3915 | 0
How can I get this output on to a single line?
select '1' "num_ads",
(case when r.region_code = 1000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 1000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "NorthEast",
(case when r.region_code = 2000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 2000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "NorthWest",
(case when r.region_code = 3000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 3000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "SouthEast",
(case when r.region_code = 4000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 4000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "SouthWest",
(case when r.region_code = 5000 then (
select count(*) from (
select userid from user_event_stg2 where userid in (
select userid from user_region where region_code = 5000)
and messagetype = 'impression' group by userid
having count(userid) = 1) as foo) else 0 end) as "Middle of Nowhere"
from user_region u, region r
where u.region_code = r.region_code
group by r.region_code;
num_ads | NorthEast | NorthWest | SouthEast | SouthWest | Middle of Nowhere
---------+-----------+-----------+-----------+-----------+-------------------
1 | 0 | 0 | 3898 | 0 | 0
1 | 3895 | 0 | 0 | 0 | 0
1 | 0 | 3873 | 0 | 0 | 0
1 | 0 | 0 | 0 | 3915 | 0
How can I get this output on to a single line?
num_ads | NorthEast | NorthWest | SouthEast | SouthWest | Middle of Nowhere
---------+-----------+-----------+-----------+-----------+-------------------
1 | 3895 | 3873 | 3898 | 3915 | 0
---------+-----------+-----------+-----------+-----------+-------------------
1 | 3895 | 3873 | 3898 | 3915 | 0
Thanks.
SELECT num_ads, sum(...), sum(...), .... FROM ( your query here ) GROUP BY num_ads; BTW, While "SELECT '1' "num_ads" is valid syntax I recommend you use the "AS" keyword. '1' AS "num_ads" David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/pivot-query-with-count-tp5752072p5752077.html Sent from the PostgreSQL - sql mailing list archive at Nabble.com.
My prior comment simply answers your question. You likely can rewrite your query so that a separate grouping layer is not needed (or rather the group by would exist in the main query and you minimize the case/sub-select column queries and use aggregates and case instead). David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/pivot-query-with-count-tp5752072p5752078.html Sent from the PostgreSQL - sql mailing list archive at Nabble.com.
Thank you very much for your response. However, I'm unclear what you want me to substitute for sum(...)?
select '1' as "num_ads", sum(...)
from
(select a.userid from
user_event_stg2 a, user_region b
where a.userid = b.userid
and b.region_code = 1000
and a.messagetype = 'impression'
group by a.userid having count(a.userid) = 1)
group by num_ads;
from
(select a.userid from
user_event_stg2 a, user_region b
where a.userid = b.userid
and b.region_code = 1000
and a.messagetype = 'impression'
group by a.userid having count(a.userid) = 1)
group by num_ads;
I was able to eliminate that sub-select per your recommendation. That makes things a bit easier.
Thanks.
On Fri, Apr 12, 2013 at 11:29 PM, David Johnston <polobo@yahoo.com> wrote:
My prior comment simply answers your question. You likely can rewrite your
query so that a separate grouping layer is not needed (or rather the group
by would exist in the main query and you minimize the case/sub-select column
queries and use aggregates and case instead).
David J.
--
View this message in context: http://postgresql.1045698.n5.nabble.com/pivot-query-with-count-tp5752072p5752078.htmlSent from the PostgreSQL - sql mailing list archive at Nabble.com.
--
Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-sql