Interacting with Databases through the Java Persistence API - Java EE 5 Development with NetBeans 6 - page 189

We can view the data in the table by right-clicking on it and selecting View Data . At
this point a new SQL Command window is opened and an SQL query retrieving all
the data in our table is automatically executed.
As we have seen, NetBeans makes it easy to write code that inserts rows into a
database table by generating JPA code.
If we need to add additional functionality such as retrieving, updating, or deleting
data, we would need to write additional methods in our DAO. The DAO would
invoke corresponding methods on EntityManager . The following table lists some of
the most commonly used methods on EntityManager .