There seems to be (as Tom indicated) a choice of approaches:
i) rewrite max/min querys and then plan 'em
ii) provide alternate plans based on presence of certain aggregate types in the query
when I first examined this TODO item, I was really thinking about i), but I suspect that ii) is probably the best approach.
regards
Mark
Bruno Wolff III wrote:
On Thu, Nov 11, 2004 at 17:57:42 +1300,
Mark Kirkwood <[EMAIL PROTECTED]> wrote:
Your example and ones like :
SELECT max(foo), count(foo) FROM bar SELECT max(a.foo1), max(b.foo2) FROM bar1 AS a NATURAL JOIN bar2 AS b
have made me realize that the scope of "what should be optimized" is somewhat subtle.
I am inclined to keep it simple (i.e rather limited) for a first cut, and if that works well, then look at extending to more complex rewrites.
What do you think?
I don't think you should be rewriting queries as much as providing
alternate plans and letting the rest of the optimizer decided which
plan to use. If you just rewrite a query you might lock yourself into
using a poor plan.
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