WebSphere Application Server V8.5 Administration and Configuration Guide for the Full Profile

Chapter 9. Accessing relational databases from WebSphere 355

For an EJB, the sequence is:

1. An EJB performs a JNDI lookup of a data source connection factory and issues a

getConnection() request.

2. The connection factory delegates the request to a connection manager.

3. The connection manager looks for an instance of a connection pool in the application

server. If no connection pool is available, the manager uses the

ManagedConnectionFactory to create a physical, or nonpooled, connection.

Version 4 data source

WebSphere Application Server V4 provided its own JDBC connection manager to handle

connection pooling and JDBC access. This support is included with WebSphere Application

Server V8.5 to provide support for J2EE 1.2 applications. If an application chooses to use a

Version 4 data source, the WebSphere Application Server V8.5 application has the same

connection behavior as in Version 4 of the application server.

Use the Version 4 data source for the following purposes:

 J2EE 1.2 applications: All EJB beans, JDBC applications, or Version 2.2 servlets must use

the Version 4 data source.

 EJB 1.x modules with 1.1 deployment descriptor: All of these modules must use the

Version 4 data source.

9.2 Steps to define access to a database

The following steps are involved in creating a data source:

1. Verify that connection to the database server is supported by WebSphere Application

Server. Refer to the following website for more information:

http://www-304.ibm.com/support/docview.wss?rs=180&uid=swg27006921#8.5

2. Ensure that the database is created and can be accessed by the systems that will use it.

3. Ensure that the JDBC provider classes are available on the systems that will access the

database. If you are not sure which classes are required, consult the documentation for

the provider.

4. Create an authentication alias that contains the user ID and password that will be used to

access the database.

5. Create a JDBC provider. The JDBC provider gives the class path of the data source

implementation class and the supporting classes for database connectivity. This is

vendor-specific.

The information center provides information about JDBC driver support and requirements.

To determine if your provider is supported, refer to the JDBC Provider Summary article at

the following website:

http://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=/com.ibm.websphe

re.nd.doc/ae/udat_minreq.html