English abstract
XML benchmarks are tools used for measuring and evaluating the performance of new XML developments such as XML/RDBMS/00 mapping techniques and XML storages. The 3D XML benchmark (3D~XBench) extends the existing XML benchmarks by offering a mechanism to measure the impact of varying three characteristics (dimensions) of the underlying XML dataset: the size (number of nodes), the breadth (fanouts), and the depth (number of levels in the XML tree). The evaluation process is then done by executing pre-defined query-set over the benchmark's dataset members where the performance of the new development is compared against the performance of some existing techniques.
Yet, none of the existing XML benchmarks seems to directly investigate the effect of sought data location on the query performance. This research is a step towards covering that aspect by investigating the rationale of adding the Data Dimension (DD) to the 3D-XBench testable features. For this, a new set of queries was added to the query-set of the 3D~XBench to test the effect of changing the location of the sought records.
To evaluate the consequence of the new extension, the evaluation process of the 3D XML Benchmark was re-executed after formulating a new set of XQuery's to be added to the existing one. The entire new query-set is aimed to measure the effect of the sought data location on the query performance over different query type and mapping techniques using different XML database categories. The experimental results show that the Data Dimension (DD) has a sensible influence on the query elapsed time with respect of database structure (depth, breadth, size) and query categories. Also the performance of different mapping approaches (single vs. multiple) have produced different results for the same XQuery types when executed over different portions of each XML database. This implied that the added DD functionality should be well considered during any XML evaluation process, and thus DD can form the 4th dimension in the 3DX~Bench Benchmark.
Finally, a further research can be carried out in this direction by investigating the effectiveness of the new extension on the Native XML databases management systems. This can be done by repeating what was done on the extended 3D XML benchmark to benchmark of the Native XML systems.
