On Thu, 2006-01-12 at 11:00, Ottó Havasvölgyi wrote: > Hi, > > I think it would be sufficient only for views. In other cases the > programmer can optimize himself. But a view can be a join of other > tables, and it is not sure that all of them are always needed. It all > depends on what I select from the view. The idea that you could throw away joins only works for outer joins. I.e. if you did: select a.x, a.y, a.z from a left join b (on a.id=b.aid) then you could throw away the join to b. But if it was a regular inner join then you couldn't know whether or not you needed to join to b without actually joining to b...
