When applying access intent policies to Enterprise JavaBeans (EJB)
methods, consider the following issues.
- Start by configuring the default access intent policy for an entity. After
your application is built and running, you can more finely tune certain access
paths in your application using application profiling or method-level access
intent.
- Don't mix access types. Avoid using both pessimistic and optimistic
policies in the same transaction. For most databases, pessimistic and optimistic
policies use different isolation levels. This can result in multiple database
connections, which prevents you from taking advantage of the performance benefits
possible through connection sharing.
- Take care when applying wsPessimisticUpdate-NoCollision. This
policy does not ensure data integrity. No database locks are held, so concurrent
transactions can overwrite each other's updates. Use this policy only if you
can be sure that only one transaction will attempt to update persistent store
at any given time.