Deploying data access applications

Deploying a data access application includes more than installing your web application archive (WAR) or enterprise archive (EAR) file onto a server. Deployment can include tasks for configuring your application to use the data access resources of the server and overall runtime environment.

1. If your RDB configuration does not exist, do the following steps:
   1. Create a database to hold the data.
   2. Create tables required by your application.

      If your application uses container managed persistence (CMP) entity beans to access the data

      You can create the tables using the data definition language (DDL) generated from the enterprise bean configuration. For more information, see the topic, Recreating database tables from the exported table data definition language.

      If your application uses bean managed persistence (BMP) entity beans, or does not use entity beans

      You must use your database server interfaces to create the tables.

      The Enterprise JavaBeans (EJB) to RDB Mapping wizard of an assembly tool is also used to create your database tables for either type of entity bean. Select the top-down mapping option in the wizard. However, this option does not give you direct control in naming the RDB elements or choosing column types. Additionally, because the top-down process is automatic, it might not provide mappings to reflect the precise relationships that you intend.

      If you use Rational® Application Developer, consult the documentation about the mapping wizard. To learn about all of your assembly tool options, see the assembly tools topic in this documentation.

   3. Check the data source minimum required settings by vendor to see any database vendor requirements for connecting to an application server. See the topic, Data source minimum required settings, by vendor, for instructions.
2. Optional: Map your entity beans to the database tables through the meet-in-the-middle mapping option of an assembly tool.
   Complete this step only if you did not create your database schema through the top-down mapping option, did not generate your mapping relationships through bottom-up mapping, or did not generate mappings during the application assembly process. For information about the top-down mapping option see the documentation for Rational Application Developer.
3. Install your application onto the application server.
   See the topic, Installing enterprise application files. When you install the application, you can alter data access settings that were made during application assembly, or, if they were omitted from the assembly process, set them for the first time. These settings include resource bindings and resource authentication aliases, which are addressed in the following substeps:
   1. Bind application resource references to the data sources, or other resource objects, that provide database connectivity.
      For details on the concept of binding, see the topic, Data source lookups for enterprise beans and web modules.

      Tip: After deployment, you can use the WebSphere® Application Server administrative console to alter resource bindings. Click Applications > Application Types > Webphere enterprise applications > application_name, and select the link to the appropriate mapping page. For example, if you want to alter the binding of an EJB module resource, you might click Map data sources for all 2.x CMP beans. For a web module resource, click Resource references.
   2. Define authentication alias data for resources that must be authenticated with the backend through container-managed authorization.
      In this security configuration, WebSphere Application Server performs EIS signon for data source or connection factory connections. Consult the topic, J2EE connector security for detailed reference on resource authentication.
4. Start the deployed application files using the administrative console, the wsadmin scripting tool startApplication command, or your own Java program.
5. Save the changes to your administrative configuration.
6. Test the application. For example, point a web browser at the URL for a deployed application and examine the performance of the application.

Results

When you deploy an application that uses a DB2® UDB for IBM® i back-end database, you might find the following exception in the SystemOut.log file:

PMGR6022E: Error using adapter to create or execute an Interaction

This type of error indicates that you deployed an application with container-managed persistence (CMP) enterprise beans that were originally configured to access a DB2 database on Windows, Linux®, or a supported UNIX system. Using the administrative console, uninstall the affected CMP applications, then reinstall the applications with the new database setting. Remember to select Deploy enterprise beans; on the EJB deploy panel, select the appropriate version of your DB2 UDB for IBM i database.

Tip: This topic references one or more of the application server log files. As a recommended alternative, you can configure the server to use the High Performance Extensible Logging (HPEL) log and trace infrastructure instead of using SystemOut.log , SystemErr.log, trace.log, and activity.log files on distributed and IBM i systems. You can also use HPEL in conjunction with your native z/OS® logging facilities. If you are using HPEL, you can access all of your log and trace information using the LogViewer command-line tool from your server profile bin directory. See the information about using HPEL to troubleshoot applications for more information on using HPEL.