Avoiding Unnecessary Ordering Operations in XPath
نویسندگان
چکیده
We present a sound and complete rule set for determining whether sorting by document order and duplicate removal operations in the query plan of XPath expressions are unnecessary. Additionally we define a deterministic automaton that illustrates how these rules can be translated into an efficient algorithm. This work is an important first step in the understanding and tackling of XPath/XQuery optimization problems that are related to ordering and duplicate removal.
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تاریخ انتشار 2003