Re: Preventing index scans for non-recoverable index AMs

On Wed, 2008-12-17 at 17:10 -0600, Kenneth Marshall wrote:
> On Wed, Dec 17, 2008 at 06:07:41PM -0500, Jaime Casanova wrote:
> > On Wed, Dec 17, 2008 at 5:47 PM, Kenneth Marshall <ktm@rice.edu> wrote:
> > > Rebuilding a hash index for the case
> > > for which it is preferred (large, large tables) would be excrutiating.
> > >
> > 
> > there's such a situation?
> > 
> As of 8.4, yes.
> 

My understanding was that the hash index type never supported
recoverability, and could require a rebuild on power failure.

If it's not written to WAL before the data page changes, how could it be
safe for recovery? The tuple inserts are logged, so during recovery the
tuple would be put in the table but the index would not be updated.

What am I missing?

Regards,Jeff Davis