Context-Preserving XQuery Fusion



Purpose

Fusion is a known technique for improving the efficiency by removing unnecessary intermediate data from the computation. Although it has been applied to optimize query languages such as SQL and object query languages, it remains as a challenge to implement fusion for XQuery optimization. This is because XQuery has more complicated semantics; it is context sensitive and requires preservation of document order. In this project, we propose, as far as we are aware, the first XQuery fusion that can deal with both the document order and the context of XQuery expressions. More specifically, we carefully design a context representation of XQuery expressions based on the Dewey order encoding, develop a context-preserving XQuery fusion for ordered trees by static emulation of the XML store.

Prototype system

Our XQuery fusion has been implemented. You can download our prototype system. This is a binary distribution for Mac OS X.
  • xfusion-0.5.0-mac.tgz (430KB, MD5: 274efa33ea2d7af91f62555d14f1e4b2, June 21 2010)
    Last modified on June 2010.