You can specify a non-transactional database connection in any of these ways:
Check the Non-Transactional Connections box on the New JDBC Connection Pool or Edit Connection Pool page in the Administration Console. The default is unchecked. For more information, click the Help button in the Administration Console.
Specify the ----nontransactionalconnections option in the asadmin create-jdbc-connection-pool command. For more information, see the Oracle GlassFish Server 3.0.1 Reference Manual.
asadmin set domain1.resources.jdbc-connection-pool.DerbyPool.non-transactional-connections=true
For more information, see the Oracle GlassFish Server 3.0.1 Reference Manual.
Use the DataSource implementation in the GlassFish Server, which provides a getNonTxConnection method. This method retrieves a JDBC connection that is not in the scope of any transaction. There are two variants.
public java.sql.Connection getNonTxConnection() throws java.sql.SQLException
public java.sql.Connection getNonTxConnection(String user, String password) throws java.sql.SQLException
Create a resource with the JNDI name ending in __nontx. This forces all connections looked up using this resource to be non transactional.
Typically, a connection is enlisted in the context of the transaction in which a getConnection call is invoked. However, a non-transactional connection is not enlisted in a transaction context even if a transaction is in progress.
The main advantage of using non-transactional connections is that the overhead incurred in enlisting and delisting connections in transaction contexts is avoided. However, use such connections carefully. For example, if a non-transactional connection is used to query the database while a transaction is in progress that modifies the database, the query retrieves the unmodified data in the database. This is because the in-progress transaction hasn’t committed. For another example, if a non-transactional connection modifies the database and a transaction that is running simultaneously rolls back, the changes made by the non-transactional connection are not rolled back.
Here is a typical use case for a non-transactional connection: a component that is updating a database in a transaction context spanning over several iterations of a loop can refresh cached data by using a non-transactional connection to read data before the transaction commits.