On Fri, 2006-05-12 at 12:22 +0200, Martijn van Oosterhout wrote: > On Thu, May 11, 2006 at 06:37:03PM -0500, Jim C. Nasby wrote: > > On Tue, May 09, 2006 at 10:37:04PM +0200, Martijn van Oosterhout wrote: > > > Note that the resulting times still include the overhead actually > > > incurred, I didn't filter it out. I want the times to remain reflecting > > > reality as closely as possible. > > > > If we actually know the overhead I think it'd be very useful at times to > > be able to remove it, especially if you're actually trying to compare to > > the planner estimates. Maybe worth adding an option to the command? > > It's not quite as easy as that unfortunatly. Each node can estimate how > much overhead was incurred on that node. However, each node also > includes as part of its timing the overhead of all its decendant nodes. > So to really remove the overhead, the top-level would have to recurse > through the whole tree to decide what to remove.
Agreed -- Simon Riggs EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
