Re: remove some rows from resultset

should work. you could move b1 out of the sub query and add a normal where
clause to make the syntax nicer. Might also matter for the query plan.
other than that i don't see any bumps. It's good that you placed
"b2.org_specific_rule = true" in the join clause so that the left join
works properly.
why the mixed feelings?

WBL

2012/4/19 Ondrej Ivanič <ondrej(dot)ivanic(at)gmail(dot)com>

> Hi,
>
> I have the following table:
> org_id | contract_name | org_specific_rule | count
> ----------+------------------+-------------------+-------
> smpj28p2 | Group 123 | f | 3
> smpj28p2 | Group 2 | f | 3
> smpj28p2 | Group 2 | t | 9
> smpj28p2 | Group 1 | f | 1
> w37mtn4r | Group 123 | f | 26
> w37mtn4r | Group 2 | f | 56
> w37mtn4r | Group 1 | f | 55
>
> Based on org_specific_rule and (org_id, contract_name) I need to transform
> this:
> smpj28p2 | Group 2 | f | 3
> smpj28p2 | Group 2 | t | 9
>
> to
> smpj28p2 | Group 2 | 9
>
> in other words:
> - if org_specific_rule = t then update "count" value in row where
> org_specific_rule = f to value from this row (3 was updated to 9)
> - remove org_specific_rule column
>
> I have query which does everything but I have mixed feelings about it:
> select
> b1.org_id, b1.contract_name, coalesce(b2.count, b1.count) as count
> from (select * from billing where org_specific_rule = false) as b1
> left join billing b2 on
> b1.org_id = b2.org_id
> and b1.contract_name = b2.contract_name
> and b2.org_specific_rule = true
> order by 1,2;
>
> org_id | contract_name | count
> ----------+------------------+----------
> smpj28p2 | Group 123 | 3
> smpj28p2 | Group 2 | 9
> smpj28p2 | Group 1 | 1
> w37mtn4r | Group 123 | 26
> w37mtn4r | Group 2 | 56
> w37mtn4r | Group 1 | 55
>
> Any ideas?
>
> --
> Ondrej Ivanic
> (ondrej(dot)ivanic(at)gmail(dot)com)
>
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