Re: tuptoaster.c must *not* use SnapshotAny

Jan Wieck wrote:
> Bruce Momjian wrote:
> >
> > Agreed. I think that was the reason we kept TOAST and large objects,
> > because large objects were designed for random read-write. If we can
> > get large objects to auto-delete, probably with pg_depend, we can then
> > use them seamlessly with BLOB I/O routines.
>
> Not entirely. BLOB's should have copy semantics, so that
> doing
>
> INSERT INTO tab1 SELECT id, blob_column FROM tab2 ...
>
> and subsequently changing the blob in either tab1 or tab2
> does NOT change the blob in the other table. Currently, even
> if you make the pg_depend stuff smart enough to let the blob
> live until all references are gone, the two tables would
> share the same blob. And that's not only IMHO wrong, it's
> also incompatible to Oracle :-)

Yes, we have to add duplication large object stuff hard-wired to that new data
type.

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