Re: [BUGS] BUG #5231: SELECT DISTINCT poorly implemented vs SELECT ... GROUP BY

2009-12-03 Thread Alvaro Herrera
Thomas Hamilton wrote: > When run against a large dataset with a small number of distinct results > HashAggregate is an order of magnitude more efficient! > > Since the spec does not require DISTINCT to return sorted results, I don't > believe Sort ... Unique will ever be more efficient than Hash

Re: [BUGS] BUG #5231: SELECT DISTINCT poorly implemented vs SELECT ... GROUP BY

2009-12-03 Thread Joshua Tolley
On Thu, Dec 03, 2009 at 03:56:05PM +, Thomas Hamilton wrote: > > The following bug has been logged online: > > Bug reference: 5231 > Logged by: Thomas Hamilton > Email address: thomashamilto...@yahoo.com > PostgreSQL version: 8.3.8 > Operating system: Ubuntu 4.2.4 > Descr

[BUGS] BUG #5231: SELECT DISTINCT poorly implemented vs SELECT ... GROUP BY

2009-12-03 Thread Thomas Hamilton
The following bug has been logged online: Bug reference: 5231 Logged by: Thomas Hamilton Email address: thomashamilto...@yahoo.com PostgreSQL version: 8.3.8 Operating system: Ubuntu 4.2.4 Description:SELECT DISTINCT poorly implemented vs SELECT ... GROUP BY Details: