RE: TOAST (was: BLOB)

> -----Original Message-----
> From: pgsql-sql-owner(at)hub(dot)org [mailto:pgsql-sql-owner(at)hub(dot)org]On Behalf
> Of Jan Wieck
>
> > Hello
> >
> > I would like to know
> > - how to create under psql a BLOB field in sql language
> > - how store a value (and not a file) in sql language
> > - the maximum size of the BLOB field
>
> For now (and 7.0), there is no way to have rows >8K in a
> regular table.
>
> But I'm actually making alot of progress in breaking it.
> Seems we'll get rid of this restriction in 7.1.
>
> To share some info with the other developers:
>
> I experienced some trouble with occational "Deadlock"
> detections, when using multiple processes hammering on the
> toaster. But I was able to reproduce the same error with a
> plain 7.0 and "text" attributes (only far less frequent).
> Seems there's something wrong in our deadlock detection
> algorithm.
>

Does the trouble mean that "Deadlock" message was issued for
non-deadlock cases ?

> Another thing is, that ISTM that index's never shrink on
> vacuum. One requirement of TOAST is, that the secondaries
> tables index-OID is remembered in the external reference, so
> the ref can be passed around in the entire backend and
> whenever needed, it's real value can be fetched quickly by an
> index scan. Thus, it's not possible to drop/recreate an index
> on that right now. Seems we need a "REBUILD INDEX" utility or
> the like.
>

REINDEX command could do it in a sense.
However current implementation couldn't guarantee the existence
of proper index in case of abort. Proper implementation would
require the standard transactional control mechanism to handle
relation files such as new naming rule of relation files....

Regards.

Hiroshi Inoue
Inoue(at)tpf(dot)co(dot)jp