Re: PG_PAGE_LAYOUT_VERSION 5 - time for change

Zdenek Kotala <Zdenek(dot)Kotala(at)Sun(dot)COM> writes:

> 3) TOAST modification
> a) TOAST table per attribute
> b) replace chunk id with offset+variable chunk size
> c) add column identification into first chunk
>
> Thats all. I think infomask/infomask2 shuffle flag should be done. TOAST
> modification complicates in-place upgrade.

I don't think TOAST table per attribute is feasible You would end up with
thousands of toast tables. It might be interesting as an option if you plan to
drop the column but I don't see it as terribly interesting.

What seemed to make sense to me for solving your problem was including the
type oid in the toast chunks. I suppose attribute number might be just as good
-- it would let you save upgrading chunks for dropped columns at the expense
of having to look up the column info first.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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