Re: Very specialised query

Список
Период
Сортировка
От Matthew Wakeling
Тема Re: Very specialised query
Дата
Msg-id alpine.DEB.2.00.0903301719230.21772@aragorn.flymine.org
обсуждение исходный текст
Ответ на Very specialised query  (Matthew Wakeling)
Ответы Re: Very specialised query  (Віталій Тимчишин)
Список pgsql-performance
Дерево обсуждения
Very specialised query  (Matthew Wakeling, )
 Re: Very specialised query  ("Kevin Grittner", )
 Re: Very specialised query  (Tom Lane, )
  Re: Very specialised query  (Matthew Wakeling, )
 Re: Very specialised query  (Matthew Wakeling, )
  Re: Very specialised query  (Tom Lane, )
 Re: Very specialised query  (Віталій Тимчишин, )
  Re: Very specialised query  (Matthew Wakeling, )
   Re: Very specialised query  (Tom Lane, )
    Re: Very specialised query  (Matthew Wakeling, )
    Re: Very specialised query  (Matthew Wakeling, )
     Re: Very specialised query  (Віталій Тимчишин, )
      Re: Very specialised query  (Matthew Wakeling, )
       Re: Very specialised query  (Віталій Тимчишин, )
        Re: Very specialised query  (Matthew Wakeling, )
 Re: Very specialised query  (Dimitri Fontaine, )
  Re: Very specialised query  (Matthew Wakeling, )
 Re: Very specialised query  ("Marc Mamin", )
  Re: Very specialised query  (Matthew Wakeling, )
   Re: Very specialised query  ("Marc Mamin", )
    Re: Very specialised query  (Matthew Wakeling, )
 Re: Very specialised query  (Matthew Wakeling, )
  Re: Very specialised query  (Віталій Тимчишин, )
   Re: Very specialised query  (Matthew Wakeling, )
    Re: Very specialised query  (Matthew Wakeling, )
     Re: Very specialised query  (Matthew Wakeling, )
      Re: Very specialised query  (Craig Ringer, )
 Re: Very specialised query  ("Marc Mamin", )
  Re: Very specialised query  (Matthew Wakeling, )
On Mon, 30 Mar 2009, Віталій Тимчишин wrote:
> select
> case when n == 1 then id1 else id2 end,
> case when n == 2 then id1 else id2 end
>
> from (
>    ... a, (values (1),(2)) b(n)

Yeah, that's nice.

However, it is still the case that we can't trust the database to choose
the correct plan. It is currently only choosing the correct plan now by
chance, and some time later it may by chance switch to one that takes 40
minutes.

I'll certainly add it to my list of possibilities.

Matthew

--
 Jadzia: Don't forget the 34th rule of acquisition: Peace is good for business.
 Quark:  That's the 35th.
 Jadzia: Oh yes, that's right. What's the 34th again?
 Quark:  War is good for business. It's easy to get them mixed up.

В списке pgsql-performance по дате отправления:

Предыдущее
От: Scott Carey
Дата:
Сообщение: Re: Trying to track down weird query stalls
Следующее
От: Matthew Wakeling
Дата:
Сообщение: Re: Very specialised query