Re: Measuring the Query Optimizer Effect: Turning off the QO?

Поиск
Список
Период
Сортировка
От Tom Mercha
Тема Re: Measuring the Query Optimizer Effect: Turning off the QO?
Дата
Msg-id AM6PR04MB55445BB12D563CE72A426295F4F60@AM6PR04MB5544.eurprd04.prod.outlook.com
обсуждение исходный текст
Ответ на Re: Measuring the Query Optimizer Effect: Turning off the QO?  (Andrew Gierth <andrew@tao11.riddles.org.uk>)
Список pgsql-general
On 08/07/2019 16:23, Andrew Gierth wrote:
>>>>>> "Tom" == Tom Mercha <mercha_t@hotmail.com> writes:
> 
>   Tom> Hi All
> 
>   Tom> As we know, a query goes through number of stages before it is
>   Tom> executed. One of these stages is query optimization (QO).
> 
> That's not really true at all. One of the stages is query _planning_,
> which takes the (rewritten) query as input and converts it to something
> that the executor can take action on. There isn't actually any separate
> "optimization" phase.
> 

Hi

I was just loosely speaking - I am merely referring to the concept that 
a query can be optimized vs unoptimized. Of course it follows that we 
have a phase or a subset of stages which are responsible for this purpose.

В списке pgsql-general по дате отправления:

Предыдущее
От: Peter Geoghegan
Дата:
Сообщение: Re: REINDEX : new parameter to preserve current average leaf densityas new implicit FILLFACTOR
Следующее
От: Peter Geoghegan
Дата:
Сообщение: Re: REINDEX : new parameter to preserve current average leaf densityas new implicit FILLFACTOR