At 2013-03-27 13:26 +0000, deBakker, Bas wrote:
Wouldn't that be equivalent to
for $a in expr1, $b in expr2, $c in expr3[$a = $b + .]
return $a
Thank you, Bas, yes I grant that your expression is equivalent to mine.
I failed to acknowledge that tuples are only created when there is a
binding value for every member of the tuple.
I appreciate the clarification.
. . . . . . . . Ken
Bas
-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of G. Ken Holman
Sent: Wednesday, March 27, 2013 14:19
To: [email protected]
Subject: Re: [xquery-talk] where clause
At 2013-03-27 08:31 -0400, 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?
I can see no difference off hand when creating 1-tuples, as a
1-tuple is essentially just a sequence.
However, when creating n-tuples (either with the "at" keyword as you
say or with other bound variables in your expression), the where
clause acts on the tuple, not just on a set of values. Here is a
3-tuple expression example:
for $a in expr1, $b in expr2, $c in expr3
where $a=$b+$c
return $a
I hope this is helpful.
. . . . . . . . Ken
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