An Experimental Study on Query Processing Efficiency of Native-XML and XML-enabled Relational Database Systems

With XML becoming a standard for semi-structured documents on the web and a standard for data exchange between different systems in e-commerce and e-business, some database companies are adding XML support to their existing database systems, while on the other hand some other companies coming out with pure or native database systems for XML. In this paper, the present an experimental study on the query processing efficiency of a native-XML database and an XML-enabled database on a selected set of queries including operations from text processing, DML and relation algebra. The experiments are conducted on two wellknown commercial database systems using the web interfaces based on HTTP. The cost metrics we used are CPU time, the number of logical reads, and the number of physical reads. The queries were run on identical machines for 3 different sizes of documents with and without indexing. A subset of experiment results was given and overall results are discussed.