Re: Is it possible in PostgreSQL?

Moving thread over to SQL list as it belongs there.

Bronx: This certainly is possible, but IMO, not in one query. Actually doing it will be relatively complex. For purposes of maintenance, I am thinking that doing this would be better handled by wrapping at least one view.

CREATE VIEW sales_pre_proc AS
SELECT name, quantity, to_char("date", 'YYYY') AS year, to_char("date", 'MM') FROM sales;

This is needed for the group by statement below to function properly:
CREATE VIEW sales_month_summary AS
SELECT name, sum(quantity) AS quantity, year, month from sales_pre_proc
GROUP BY name, year, month;

This will give you a view that will have the sum information. Now we just have to create the statement which will create the pivot effect. I understand that there is something under contrib/tablefunc for this, but I do not have it on my system (cygwin), at the moment. Perhaps someone else can help.

Failing that, you can write your own function to return each row. I was working on a quick proof of concept but it was not working properly.

Best Wishes,
Chris Travers

----- Original Message -----
From: Bronx
To: pgsql-admin(at)postgresql(dot)org
Sent: Tuesday, January 13, 2004 6:58 AM
Subject: [ADMIN] Is it possible in PostgreSQL?

Hi,
I've got problem with one specific query. I've got the table
with many of rekords like these:

name | quantity | date
-------------------------------------------------------
aaa 2 2003-04-01
bbb 4 2003-04-12
ccc 5 2003-05-12
aaa 3 2003-01-14
aaa 1 2003-12-09
bbb 9 2003-08-08

and so on ...

Does anybody know how make query which return grouped
records by month of year and name (also sum of quantity).
It is possible to make a query whitch return something like that:

name | 01 | 02 | 03 | 04 | ... | 12 (months)
------------------------------------------------
aaa x x x x ... x
bbb x x x x ... x
ccc x x x x ... x

where x means sum of quantity in month.
It is possible to make it in one query?
I know that in Access is construction : PIVOT.

Thanks
Adam