On Fri, Dec 16, 2005 at 04:16:58PM +1300, Mark Kirkwood wrote: > Craig A. James wrote: > > > > >What would be cool would be some way the developer could alter the plan, > >but they way of doing so would strongly encourage the developer to send > >the information to this mailing list. Postgres would essentially say, > >"Ok, you can do that, but we want to know why!" > > > > Yeah it would - an implementation I have seen that I like is where the > developer can supply the *entire* execution plan with a query. This is > complex enough to make casual use unlikely :-), but provides the ability > to try out other plans, and also fix that vital query that must run > today..... Being able to specify an exact plan would also provide for query plan stability; something that is critically important in certain applications. If you have to meet a specific response time requirement for a query, you can't afford to have the optimizer suddenly decide that some other plan might be faster when in fact it's much slower. -- Jim C. Nasby, Sr. Engineering Consultant jnasby@xxxxxxxxxxxxx Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
