Planning to upgrade database applications and routines

Planning to upgrade your database applications and routines requires that you review all of the applicable pre-upgrade tasks, upgrade prerequisites, upgrade tasks, and post-upgrade tasks.

To create an upgrade plan for your database applications and routines:

1. Write the upgrade plan for database applications, using all the details that apply to your environment:

   Table 1. Upgrade plan details for database applications.

   Upgrade plan	Details
   Prerequisites	Ensure that you: meet the installation prerequisites. meet the development software requirements. resolve any support issues in Upgrade essentials for database applications during the upgrade. meet all prerequisites for the upgrade task and subtasks, especially obtaining required Db2® authorization.
   Pre-upgrade tasks	Include the following tasks: Upgrade Db2 clients or install the Db2 version 12.1 application driver. Test your database applications in a Db2 version 12.1 testing environment. If your applications run successfully, the rest of the upgrade steps are not required. In addition, check the list of Pre-upgrade tasks for database applications and routines for optional tasks that you might want to perform for your environment. Even if your current operating system and development software are supported, consider including the following tasks to improve application performance: Upgrade your operating system to the latest supported level Upgrade your development software to the latest supported level
   Upgrade task	You must include these steps: Modify your application code to support changes in Db2 version 12.1 and to remove use of functionality that is discontinued in Db2 version 12.1. Modify your application to support changes specific to the development environment. Rebuild all database applications after completing your modifications. Test your database applications using Db2 version 12.1. Review the following upgrade tasks to determine the additional steps that are required by your development environment to upgrade database applications: Upgrading embedded SQL applications Upgrading CLI applications Upgrading Java applications that use IBM Data Server Driver for JDBC and SQLJ Upgrading ADO.NET applications Upgrading scripts
   Post-upgrade tasks	Perform the recommended Post-upgrade tasks for database applications and routines, especially: Tune performance of your database applications. Remove the use of Deprecated or discontinued functionality that affects Db2 server upgrades. Adopting new Db2 12.1 functionality in database applications and routines where appropriate.

2. Write the upgrade plan for routines, using all the details that apply to your environment:

   Table 2. Upgrade plan details for routines.

   Upgrade plan	Details
   Prerequisites	Ensure that you: meet the development software requirements.. resolve any support issues in Upgrade essentials for routines during the upgrade. meet all prerequisites for the upgrade task and subtasks, especially obtaining required Db2 authorization.
   Pre-upgrade tasks	Include the following task: Test your routines in a Db2 version 12.1 testing environment. If your routines run successfully, the rest of the upgrade steps are not required. In addition, check the list of Pre-upgrade tasks for database applications and routines for optional tasks that you might want to perform for your environment. Even if your development software is supported, consider upgrading your development software to the latest supported level.
   Upgrade task	You must include these steps: Modify your routines to support changes in Db2 version 12.1 and to remove use of functionality that is discontinued in Db2 version 12.1. Modify your routines to support changes specific to the development environment. Rebuild all external routines after completing your modifications. Retest your routines using Db2 version 12.1. Review the following upgrade tasks to determine the additional steps that are required by your development environment to upgrade routines: Upgrading C, C++, and COBOL routines Upgrading Java routines Upgrading .NET CLR routines
   Post-upgrade tasks	Perform the recommended Post-upgrade tasks for database applications and routines, especially: Remove the use of Deprecated or discontinued functionality that affects Db2 server upgrades Adopting new Db2 12.1 functionality in database applications and routines where appropriate

3. Combine with the upgrade plan for other components such as Db2 data server clients and Db2 servers to create an overall upgrade plan for your Db2 environment.