6.7. Summary

In this chapter, we looked at how persistent instances can be queried and retrieved from the underlying datastore using the query facilities specified in JDO. We looked at two parts of the facility, the API and JDOQL, which is a Java-like syntax for specifying the query filters. We looked at detailed examples that showed different features of the API and JDOQL that are available to developers.

In Chapter 7, we look at architecture scenarios and how JDO fits into different environments.