Xcerpt Open Issues : No 1 , February 2 nd , 2006 Node Identity in Xcerpt
نویسنده
چکیده
Xcerpt so far has considered identity a function of the structure and value of a data item (extensional identity). In this paper another approach to identity, viz. surrogate or object identity as in object-oriented programming languages and databases is investigated. It is demonstrated how this approach can solve a number of problems raised by the current Xcerpt, including object updates and their tracking as well as unrestricted occurrence queries such as “How many title elements occur at any depth in section 1?”.
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