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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