Three Cases for Query Decorrelation in XQuery

نویسندگان

  • Norman May
  • Sven Helmer
  • Guido Moerkotte
چکیده

We present algebraic equivalences that allow to unnest nested algebraic expressions for order-preserving algebraic operators. We illustrate how these equivalences can be applied successfully to unnest nested queries given in the XQuery language. Measurements illustrate the performance gains possible our approach.

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تاریخ انتشار 2003