For access to relational databases, applications use the
JDBC drivers and data sources that you configure for the application
server.
Before you begin
Each vendor database requires different JDBC driver implementation
classes for JDBC connectivity. A JDBC provider encapsulates those
vendor-specific driver files. Through the data source that you associate
with the JDBC provider, an application server obtains and manages
the physical connections for transactions between applications and
the database.
Determine the version of data source that you need
according to the API specification of your applications.
- Data sources (WebSphere Application Server
Version 4) are for use with the Enterprise JavaBeans (EJB) 1.0
specification and the Java Servlet 2.2 specification.
- Data sources of the latest standard version are for use with applications
that implement the more advanced releases of these specifications.
Important: If
you connect to DB2 for z/OS through the JDBC Universal JDBC Driver,
follow the steps that are outlined in
Using the DB2 Universal JDBC Driver to access DB2 for z/OS.
This article gives detailed instruction on installing the JDBC driver
and related files, plus activating required JDBC properties.
Results
If you use the DB2 JDBC Universal Driver, you might experience
data source failures that the application server JVM log does not
document. Check the DB2 database log or the WebSphere Application
Server JDBC trace log (if JDBC trace was active). You might find that
a bad authentication credential is the cause of failure. Currently
the DB2 JDBC Universal Driver does not identify or surface the errors
that are produced by non-valid authentication credentials in a proper
or consistent way.
Even if you receive information about a bad
credential, check the database and JDBC trace logs. These logs provide
more reliable, detailed error data on authentication failures.
Tip: The JDBC trace log exists only if the JDBC trace service
is active during server start up. Activate the service in the administrative
console. For more information, see
Enabling trace at server startup.
Specify
WAS.database as the trace group and select
com.ibm.ws.db2.logwriter as
the trace string.