(forwarding Daniela's message) Michael,
I think the ones with grouby and a where after the groupby are impossible to rewrite in general (remember this from my optimizing SQL days). In this case the WHERE is the good old HAVING clause of SQL. Something along the lines of for $x in blah for $y in blah group by $z:= $x/a, $t:= $y/b where $z+$t >25 return $z I am putting an informal syntax, obviously. Another case is when the COUNT clause exists. You cannot move the where up and down in the tuple stream in such a case. for $x in Blah1 for $y in Blah2 count $i where $x/a eq $y/b return something using $i HTH Dana On Mar 27, 2013, at 5:31 AM, Michael Sokolov wrote:
I'm trying to come up with examples in which "where" clauses cannot be rewritten as XPath predicates. So far, the ones I have all involve an "at" counter. Are there others? -- Michael Sokolov Senior Architect Safari Books Online _______________________________________________ [email protected] http://x-query.com/mailman/listinfo/talk
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