Chapter 14. Querying with HQL and JPA QL

Queries are the most interesting part of writing good data access code. A complex query may require a long time to get right, and its impact on the performance of the application can be tremendous. On the other hand, writing queries becomes much easier with more experience, and what seemed difficult at first is only a matter of knowing some of the more advanced features.

If you've been using handwritten SQL for a number of years, you may be concerned that ORM will take away some of the expressiveness and flexibility that you're used to. This isn't the case with Hibernate and Java Persistence.