Re: dropping column prevented due to inherited index - Mailing list pgsql-hackers

From Amit Langote
Subject Re: dropping column prevented due to inherited index
Date
Msg-id CA+HiwqELTB1HnVPCWTYHgT73+aXibWg0Fz7QCGfeMr5g0pVqUg@mail.gmail.com
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In response to Re: dropping column prevented due to inherited index  (Michael Paquier <michael@paquier.xyz>)
Responses Re: dropping column prevented due to inherited index
List pgsql-hackers
Hello,

On Fri, Oct 4, 2019 at 5:57 PM Michael Paquier <michael@paquier.xyz> wrote:
>
> On Thu, Oct 03, 2019 at 09:18:12AM -0300, Alvaro Herrera wrote:
> > Hmm.  I wonder if we shouldn't adopt the coding pattern we've used
> > elsewhere of collecting all columns to be dropped first into an
> > ObjectAddresses array, then use performMultipleDeletions.
>
> +1.  That's the common pattern these days, because that's more
> performant.

Actually I don't see the peformMultipleDeletions() pattern being used
for the situations where there are multiple objects to drop due to
inheritance.  I only see it where there are multiple objects related
to one table.  Maybe it's possible to apply to the inheritance
situation though, but in this particular case, it seems a bit hard to
do, because ATExecDropColumn steps through an inheritance tree level
at a time.

But maybe I misunderstood Alvaro's suggestion?

>  I think that the patch should have regression tests.

I have added one in the attached updated patch.

Thanks,
Amit

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