By designating container managed persistence (CMP) sequence
groups for entity beans, you can prevent certain types of database-related
exceptions during the run time of your Enterprise JavaBeans (EJB)
application. Specify in each group the order in which the beans update
your relational database tables.
Before you begin
When you define a sequence group, you designate it as one of two
types:
- RI_INSERT, for setting a bean persistence sequence to prevent
database referential integrity (RI) violations. See the topic Sequence grouping for container-managed persistence
in assembled EJB modules for more information.
- UPDATE_LOCK, for setting a bean persistence sequence to minimize
exceptions resulting from optimistic concurrency control
About this task
Both types of sequence groups must be created after you have
assembled the beans into an EJB module, before installing your application
on the product. If you need to edit sequence groups, uninstall the application,
make your changes with an assembly tool, and reinstall your application.
Attention: If you already selected or plan to use top-down mapping for
mapping your enterprise beans to back-end data, you do not need to
create a sequence group with an RI_INSERT type. The product does not generate an RI policy for the database
schema that it creates when you select top-down mapping.
To
learn how to complete this task see the assembly tool information
center.
What to do next
You are now ready to deploy your EJB module or combine it
with other modules into a Java EE application. For more information
about these two tasks, see the topics Installing enterprise application
files and Assembling Java EE client applications.