XQuery count()

[G. Ken Holman]

At 2009-11-09 18:55 +0000, Ricardo Queirós wrote:
>I need to count the total number of distinct 
>collections in my db (eXist XML Database).

How are you defining "distinct" in your 
situation?  There are many possible ways:  string 
value, tree structure, tree structure of string values, etc.

>How can i do this in a compact way using XQuery?

Consider using deep-equal() ... if you have two 
root nodes, say in $a and $b, you can get 
true/false with deep-equal( $a, $b ) and it will 
check the tree structure and the node values in 
the tree structure and things like attributes 
will be checked regardless of their order 
(because attributes in XML documents are unordered).

But be aware this is an "expensive" function, and 
could take up a lot of processing resources to accomplish the comparison.

I hope this helps.

. . . . . . . . . . . Ken


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