Re: Pull up sublink of type 'NOT NOT (expr)' - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Pull up sublink of type 'NOT NOT (expr)'
Date
Msg-id 16174.1542074759@sss.pgh.pa.us
Whole thread Raw
In response to Pull up sublink of type 'NOT NOT (expr)'  (Richard Guo <riguo@pivotal.io>)
Responses Re: Pull up sublink of type 'NOT NOT (expr)'  (Richard Guo <riguo@pivotal.io>)
List 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


pgsql-hackers by date:

Previous
From: "Yotsunaga, Naoki"
Date:
Subject: RE: [Proposal] Add accumulated statistics for wait event
Next
From: Michael Paquier
Date:
Subject: Re: move PartitionBoundInfo creation code