Re: pgsql: Declare assorted array functions using anycompatible not anyelem

On 11/9/20 4:29 PM, Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>> On 11/4/20 4:10 PM, Tom Lane wrote:
>>> Declare assorted array functions using anycompatible not anyelement.
>> This patch broke cross-version pg_upgrade testing.
> Uh, yeah ... didn't you get my two prior messages about that?

Yes, I did, although by the time you sent them out I'd already modified
crake.

>
>> I have cured crake
>> for the moment by having it execute this in the source database:
> I think probably the right fix is just to change that test case to
> use a different implementation function, per [1]. I'm holding off
> pushing the fix till after this week's wraps, though.

I'd be ok with that. Can we devise a fix that will work all the way back
to 9.2, which is where we start upgrade testing?

>
>> But I wonder if we really want to make it impossible to upgrade
>> databases with aggregates that contain these functions?
> If I thought that user-defined aggregates relying on array_cat were
> really a thing (and not just a test case), I'd be more concerned about
> this. But it's hard to see why users shouldn't use array_agg() instead
> of rolling their own.
>
>

Possibly something that's been migrated from before we had array_agg.

cheers

andrew