* JdbcPersistence -- It's simple and ubiquitous, and it's easier than you think.
 * Problems with OracleLobs (large objects)
 * Patterns of PrimaryKeyGeneration

Some techniques to investigate further:

 * [[http://pbeans.sourceforge.net/|pBeans]] -- also see [[http://weblogs.java.net/pub/wlg/1299|Michael Ivey's blog]]
 * [[http://www.theserverside.com/news/thread.tss?thread_id=40581|DAO vs. Hibernate]]