Re: What is wrong with hashed index usage?

On Mon, 22 Apr 2002 15:04:22 -0700
"Dann Corbit"  wrote:
> Here is where a hashed index shines:
> To find a single item using a key, hashed indexes are enormously faster
> than a btree.
> 
> That is typically speaking.  I have not done performance benchmarks with
> PostgreSQL.

Yes -- but in the benchmarks I've done, the performance different
is not more than 5% (for tables with ~ 600,000 rows, doing lookups
based on a PK with "="). That said, my benchmarks could very well
be flawed, I didn't spend a lot of time on it. If you'd like to
generate some interest in improving hash indexes, I'd like to see
some empirical data supporting your performance claims.

Cheers,

Neil

-- 
Neil Conway 
PGP Key ID: DB3C29FC