Re: Pull up sublink of type 'NOT NOT (expr)'

Поиск
Список
Период
Сортировка
От Tom Lane
Тема Re: Pull up sublink of type 'NOT NOT (expr)'
Дата
Msg-id 16174.1542074759@sss.pgh.pa.us
обсуждение исходный текст
Ответ на Pull up sublink of type 'NOT NOT (expr)'  (Richard Guo <riguo@pivotal.io>)
Ответы Re: Pull up sublink of type 'NOT NOT (expr)'  (Richard Guo <riguo@pivotal.io>)
Список pgsql-hackers
Richard Guo <riguo@pivotal.io> writes:
> Currently for quals in the form of "NOT NOT (SubLink)", this SubLink would
> not be considered when pulling up sublinks.

Yup.

> Should we give it a chance, like the attached does?

What is the argument that this occurs often enough to be worth expending
extra cycles and code space on?

If we do do something like this, I'd be inclined to make it handle
any-number-of-consecutive-NOTs, and maybe remove NOT NOT over an ANY,
not just EXISTS.  But I don't honestly think that it's worth troubling
over.  Do even the dumbest ORMs generate such code?

            regards, tom lane


В списке pgsql-hackers по дате отправления:

Предыдущее
От: "Yotsunaga, Naoki"
Дата:
Сообщение: RE: [Proposal] Add accumulated statistics for wait event
Следующее
От: Michael Paquier
Дата:
Сообщение: Re: move PartitionBoundInfo creation code