Summary

DataDirect XQuery was designed for performance and scalability, which are essential in business-critical applications. Because of our careful attention to the generating the best possible SQL to implement XQuery on any given database, as well as using the best available JDBC technology, DataDirect XQuery has exceptional performance. It generally outperforms both Java applications that create XML from database data using JDBC, SQL, and XML APIs. It also generally outperforms other XQuery implementations.

Implementing XQuery efficiently for SQL databases requires sophisticated query optimization and SQL generation algorithms. In this document, we have outlined some of the techniques DataDirect XQuery uses to generate efficient SQL. Our performance suites and our customers' experience show that these techniques are very effective. When you need more control over the SQL that is used, you can call SQL functions as XQuery external functions or use declaration options to influence the algorithms we use in generated SQL.