Heikki Linnakangas wrote:
> Tom Lane wrote:
> > Heikki Linnakangas <[EMAIL PROTECTED]> writes:
> >   
> >> I've been experimenting with the idea of a so-called Block B-Tree. The 
> >> basic idea is that instead of storing an index tuple for each heap 
> >> tuple, we store an index tuple for each heap block. This dramatically 
> >> reduces the size of an index, leading to savings on I/O.
> >>     
> >
> >   
> There's a few options that I've thought of this far:
> 1. Whenever a tuple is found dead on page X, vacuum of the index will 
> have to go to that page again to see if there's any matching tuples left.

Right now, if an index entry points to a dead tuple, we set a bit in 
the index so future lookups do not access the heap.  We could set a bit 
for block index entries that point to a page that has no live rows, and
have vacuum remove the index entry later.

  Bruce Momjian   [EMAIL PROTECTED]
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +

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