Re: [BUG] Cache invalidation for queries that contains const of temporary composite type

On Tue, Oct 3, 2017 at 12:20 AM, Maksim Milyutin <milyutinma(at)gmail(dot)com>
wrote:

> I have tested the following case:
>
> create type pair as (x int, y int);
> prepare test as select json_populate_record(null::pair, '{"x": 1, "y":
> 2}'::json);
> drop type pair cascade;
>
> execute test;
>
> -- The following output is obtained before patch
> ERROR: cache lookup failed for type 16419
>
> -- After applying patch
> ERROR: type "pair" does not exist
>
> But after recreating 'pair' type I'll get the following message:
> ERROR: cached plan must not change result type
>
> I don't know whether it's right behavior. Anyhow your point is a good
> motivation to experiment and investigate different scenarios of work with
> cached plan that depends on non-stable type. Thanks for that.
>

I think ideally, cached plan should be automatically invalidated and stored
procedure should work without error.
Not really sure if it's feasible...

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company