Re: pg_upgrade: How to deal with toast

Zdenek Kotala <Zdenek.Kotala@Sun.COM> writes:
> Tom Lane napsal(a):
>> No, it's a really horrid idea.  Nullable attributes complicate the C
>> code, and what in the world are we buying with it anyway?  Just decide
>> what the field should contain and put it in there.

> The problem what we try to solve is to perform this change during upgrade from 
> 8.3->8.4. Extra value is a problem because it requires extra space and there is 
> not free space. It is temporal solution(hack) for 8.3->8.4.

Solution of what?  The original concern you had was about
TOAST_MAX_CHUNK_SIZE changing from 8.3 to 8.4.  If that's a problem then
it has to be solved anyway, and the solution has to involve being able
to push some chunks off-page to make room.  If it's not a problem then
let's just leave the toast representation as-is till later.
        regards, tom lane