> Bruce Momjian wrote:
>
> > I disagree. By moving to another table, we don't have non-standard
> > tuples in the main table. We can create normal tuples in the long*
> > table, of identical format, and access them just like normal tuples.
> > Having special long tuples in the main table that don't follow the
> > format of the other tuples it a certain mess. The long* tables also
> > move the long data out of the main table so it is not accessed in
> > sequential scans. Why keep them in the main table?
>
> More ugly and complicated (especially for VACUUM) seems to
> me, the we need an index on these nonstandard tuples, that
> doesn't see the standard ones, while the regular indices
> ignore the new long tuples. At least if we want to delay
> reading of long values until they're explicitly requested.
>
Yes, good point. No reason to create non-standard tuples if you can
avoid it. And a separate table has performance advantages, especially
because the long tuples are by definition long and take up lots of
blocks.
-- Bruce Momjian | http://www.op.net/~candle maillist@candle.pha.pa.us | (610)
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