On 30.4.2015 19:08, Jonathan Vanasco wrote:
>
> On Apr 29, 2015, at 6:50 PM, Jim Nasby wrote:
>
>> Only because you're using UNION. Use UNION ALL instead.
>
> The difference between "union" and "union all" was negligible. the problem was
> in the subselect and the sheer size of the tables, even when we could handle it
> as an index-only scan.
>
>
> On Apr 29, 2015, at 1:18 PM, Ladislav Lenart wrote:
>
>> I would expect the overall query to return only 60F nad 55F as the most recent
>> data. No? You expect it to return 4 items when the LIMIT is only 2. Remember
>> that the overall query should be also ordered by ts and limited to 2.
>
> You're right. total mistake on my part and confusion with that. I got this
> query confused with the specifics of a similar one.
OK :-) Have you managed to solve the problem then? I am interested in your final
solution.
Thank you,
Ladislav Lenart