On Sat, 2005-09-10 at 19:25 -0400, D. Richard Hipp wrote: > Beginning with SQLite 3.2.3, the query optimizer has had > the ability to reorder tables in the FROM clause if it thinks > that doing so will make the query run faster. This has caused > a few problems for some folks. To ameliorate those > difficulties, I have now modified the query optimizer so > that it will no longer reorder tables in a join if the join > is constructed using the CROSS keyword. For additional > detail see > > http://www.sqlite.org/cvstrac/tktview?tn=1414 > http://www.sqlite.org/cvstrac/wiki?p=QueryPlans > > Thoughtful feedback on this design choice will be appreciated. > I'd like to do a release of version 3.2.6 containing this and > other changes on or before September 16. > > The rational behind using the CROSS keyword to disable an > optimization is that the CROSS keyword is perfectly > valid SQL syntax but nobody ever uses it so I figured > we can put it to use to help control the optimizer without > creating any incompatibilities.
The ticket mentions that postgres uses the same heuristic? Is there some Pg documentation that demonstrates this?
