[xquery-talk] Query Through Multiple Files
mike at saxonica.com
Mon Jan 21 21:04:08 PST 2008
> I tried using
> distinct-values(doc("1.xml"), doc("3.xml"), doc("4.xml"),
> doc("2.xml"))//title, but I got the error that there should
> be only 2 arguments.
You didn't read my example carefully enough
Firstly, you want to find the set of titles and then take the distinct
values in this set: so the "//title" part needs to inside the argument to
distinct-values(). The way you've written it, you're taking four documents,
then eliminating duplicates, then taking the title elements within those
that are left.
Secondly, if you supply a sequence to a function that expects a single
argument then you need to double the parentheses, for example
sum((1,2,3,4,5)) or distinct-values((1,2,2,4,4)). That's to make it clear
you are passing one argument which is a sequence of five integers, not five
arguments that are single integers. IN your case you've called
distinct-values() with four arguments, rather than with a single argument
that is a sequence.
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