PFC wrote:
>
> > My idea is that if an UPDATE places the new tuple on the same page as
> > the old tuple, it will not create new index entries for any indexes
> > where the key doesn't change.
>
> Basically the idea behind preventing index bloat by updates is to have
> one index tuple point to several actual tuples having the same value.
>
The idea is not to avoid index bloat, but to allow heap reuse, and having
one index entry for multiple versions of an UPDATEd row is merely an
implementation detail.
--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com
+ If your life is a hard drive, Christ can be your backup. +