On Friday 01 December 2000 00:33, Tom Lane wrote: > The rewriting is done, all right, but what's left afterward still has > references to the view, because each rule is conditional. Essentially, > the rewriter output looks like > > -- rule 1 > if (rule1 condition holds) > -- rule 2 applied to rule1 success case > if (rule2 condition holds) > apply rule 2's query > else > apply rule 1's query > else > -- rule 2 applied to rule1 failure case > if (rule2 condition holds) > apply rule 2's query > else > apply original query > > If the system were capable of determining that either rule1 or rule2 > condition will always hold, perhaps it could deduce that the original > query on the view will never be applied. However, I doubt that we > really want to let loose an automated theorem prover on the results > of every rewrite ... I think it would be better to move the test further down, to just before we actually try to do the update/insert. Maybe into the heap access routines as suggested by Andreas. -- Mark Hollomon
