Existing database systems do not provide the uniform support for both XML and Relational Data with similar storage and retrieval efficiencies. A generic data mediator provides uniform support for both XML and relational data with similar storage and retrieval efficiencies is produced; by using existing efficient schema-oblivious mapping strategies XNode and SUXCENT and free of cost available technologies: MySQL, PHPMyAdmin and PHP classes. The key to mediator approach is storing and retrieving XML documents in a relational database, providing a user interface for XML manipulation, independent of proprietorship and without doing any modification in its basic structure. After the mediator's implementation, the RDBMS becomes repository for both XML and Relational data simultaneously. The mediator has flexibility to add any proposed more efficient schema-oblivious XML mapping strategy as a new collection. The mediator can also be used as the benchmarking tool for the researchers to compare various schema-oblivious XML mapping strategies by adding a new collection. The comparative study of insertion, retrieval and query performance of these two types of mapping strategies is produced.