Re: Complete row is fetched ?

Craig Ringer wrote:
> I sometimes wonder if being able to store visibility info externally
> to a tuple in a separate file - in condensed fixed-width form - would
> be useful for performance, especially where the table has quite wide
> tuples with types that are big-ish but not TOASTable. Sure, it'd be
> more disk seeking but OTOH it'd be more likely to stick around in
> cache, could even be put on other storage, etc.

In this situation, you can always split the primary key and the other
most referenced fields out to a "thinner" version, then only join
against the rest when needed. The rows really do have to be just on the
edge of TOAST size for this to ever make sense though, given how much
overhead is taken per row just to store anything in the database.

--
Greg Smith 2ndQuadrant US Baltimore, MD
PostgreSQL Training, Services and Support
greg(at)2ndQuadrant(dot)com www.2ndQuadrant.us