Part 4. Writing queries

In part 4, we introduce data-query features and cover query languages and APIs in detail. Not all chapters in this part are written in a tutorial style; we expect you’ll browse this part of the book frequently when building an application and looking up a solution for a particular query problem.

Starting in chapter 14, we’ll talk about creating and executing queries using the basic query APIs, preparing and executing queries, and optimizing query execution. Continuing in chapter 15, we’ll cover the query languages, writing JPQL and criteria queries, retrieving data efficiently with joins, and reporting queries and subselects. Chapter 16 dives deeper into advanced query options: transforming query results, filtering collections, and query-by-criteria with the Hibernate API. Finally, chapter 17 describes customization techniques like falling back to JDBC, mapping SQL query results, customizing CRUD operations, and calling stored procedures.

After reading this part, you’ll be able to get any data you want out of your database using various querying techniques, customizing access as needed.