Re: [HACKERS][BUG] Cache invalidation for queries that contains constof temporary composite type

Hi, Alexander!

Thanks for the comments.

Please, register this patch at upcoming commitfest to ensure it wouldn't be forgotten.

Regression test changes (both .sql and .out) are essential parts of the patch.  I see no point in posting them separately.  Please, incorporate them into your patch.

OK, I'll take your advice.

Did you check this patch with manually created composite type (made by CREATE TYPE typname AS ...)?

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.

-- 
Regards,
Maksim Milyutin