Greg Stark writes:
> On Fri, Mar 16, 2012 at 3:16 PM, Tom Lane wrote:
> So I now propose reverting the earlier two patches (but not their
> regression test cases of course) and instead hacking MergeAppend plan
> building as per (2).
> As a wise man once said, "This is tricky stuff". I feel a bet
On Fri, Mar 16, 2012 at 3:16 PM, Tom Lane wrote:
>> So I now propose reverting the earlier two patches (but not their
>> regression test cases of course) and instead hacking MergeAppend plan
>> building as per (2).
As a wise man once said, "This is tricky stuff". I feel a better that
I got stuck
I wrote:
> So I now propose reverting the earlier two patches (but not their
> regression test cases of course) and instead hacking MergeAppend plan
> building as per (2).
Attached is a draft patch for that. There are several things going on
here:
* Revert the preceding two patches (except for t
I wrote:
> Yeb Havinga writes:
>> I'm having a hard time imagining that add_child_rel_equivalences is not
>> just plain wrong. Even though it will only add child equivalence members
>> to a parent eq class when certain conditions are met, isn't it the case
>> that since a union (all) is additio
Yeb Havinga writes:
> On 2012-03-15 02:29, Tom Lane wrote:
>>> There is an EquivalenceClass for each of "t1" and "t2", and if we don't
>>> do something like wrapping the constants with distinct PHVs, then
>>> add_child_rel_equivalences will end up pushing identical constants into
>>> both ECs, thu
On 2012-03-15 02:29, Tom Lane wrote:
>
> explain select * from
> (select thousand as t1, tenthous as t2 from tenk1 a
> union all
> select 42 as t1, 42 as t2 from tenk1 b) c
> order by t1, t2;
>
> There is an EquivalenceClass for each of "t1" and "t2", and if we don't
> do something like wrapp
I looked into the problem complained of here:
http://archives.postgresql.org/pgsql-bugs/2012-03/msg00016.php
It's not at all specific to custom types; you can exhibit it with
this query in the regression database:
explain select * from
(select 1 as t, unique1 from tenk1 a
union all
select 2 a
