On Wed, Jul 7, 2010 at 7:43 PM, Tom Lane wrote:
> Anyway, the way it works is that the parser generates "alias Vars" that
> refer to the join RTE, mainly because this makes life simpler for
> ruleutils. But the planner prefers to work with the "real" underlying
> columns whenever those are semant
Robert Haas writes:
> I'm lost. What's a join alias var?
Suppose we have t1 with columns a,b,c and t2 with columns d,e,f, then
consider
select a from t1 join t2 on (whatever)
select t1.a from t1 join t2 on (whatever)
In the first case the parser generates a Var that references
On Wed, Jul 7, 2010 at 6:55 PM, Tom Lane wrote:
> After some investigation I was able to simplify it to the following
> example using the regression database:
>
> select
> (select sq1) as qq1
> from
> (select exists(select 1 from int4_tbl where f1 = q2) as sq1, 42 as dummy
> from int8_tbl) sq0
Merlin sent me a test case off-list for the problem mentioned here:
http://archives.postgresql.org/pgsql-bugs/2010-07/msg00025.php
After some investigation I was able to simplify it to the following
example using the regression database:
select
(select sq1) as qq1
from
(select exists(select 1
