Re: Allowing ALTER TYPE to change storage strategy - Mailing list pgsql-hackers

On Thu, Mar 05, 2020 at 05:46:44PM -0500, Tom Lane wrote:
>I wrote:
>> If not, we probably should bite the bullet and go for #1, since
>> I have little doubt that we'll need that someday anyway.
>> The trick will be to keep down the cache invalidation overhead...
>
>Here's a version that does it like that.  I'm less worried about the
>overhead than I was before, because I realized that we already had
>a syscache callback for pg_type there.  And it was being pretty
>stupid about which entries it reset, too, so this version might
>actually net out as less overhead (in some workloads anyway).
>
>For ease of review I just added the new TCFLAGS value out of
>sequence, but I'd be inclined to renumber the bits back into
>sequence before committing.
>

LGTM. If I had to nitpick, I'd say that the example in docs should be 

   ALTER TYPE mytype SET (
       SEND = mytypesend,
       RECEIVE = mytyperecv
   );

i.e. with uppercase SEND/RECEIVE, because that's how we spell it in
other examples in CREATE TYPE etc.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services