Upgrade essentials for database applications

Changes in application development support, new functionality, discontinued functionality, and deprecated functionality might impact your database applications, scripts and tools after you upgrade them to version 11.1.

Operating system support

A complete list of supported operating systems is available at Installation requirements for Db2® database products. If your current version of operating system is unsupported, you must upgrade it before you install version 11.1.

In UNIX operating systems, only 64-bit kernels are supported. Your 32-bit instances are upgraded to version 11.1 64-bit instances.

If you upgrade to the latest version of your operating system or you install a 64-bit kernel, rebuild all database applications and external routines after you upgrade to version 11.1 so that they use the new runtime libraries in the operating system.

Development software support

Development software support has also changed. To improve performance and avoid technical support issues, rebuild your applications with the latest version of your development software. Review the changes in support for development software requirements

Application drivers

The IBM® Data Server Driver for JDBC and SQLJ includes the db2jcc.jar class file for applications that use JDBC 3.0 methods or earlier and the db2jcc4.jar class file for applications that use JDBC 4.0 or later methods or JDBC 3.0 or earlier methods. To manage the behavioral differences between the driver that supports JDBC 4.0 or later in version 9.7 and previous releases of this driver, upgrade Java™ applications that use IBM Data Server Driver for JDBC and SQLJ. See Upgrading Java applications that use IBM Data Server Driver for JDBC and SQLJ for details.

The Db2 JDBC Type 2 driver is discontinued in version 10.1. You should modify your Java applications and external routines to use the IBM Data Server Driver for JDBC and SQLJ with type 2 connections.

To manage the behavioral differences between the version of IBM Data Server Driver for JDBC and SQLJ that support JDBC 3.0 and the Db2 JDBC Type 2 driver, upgrade your Java applications that use Db2 JDBC Type 2 driver. See Upgrading Java applications that use Db2 JDBC Type 2 driver for details.

See Db2 and IBM Data Server Driver for JDBC and SQLJ levels for details about the versions of IBM Data Server Driver for JDBC and SQLJ that are delivered with every Db2 database product version and fix packs. See JDBC differences between versions of the IBM Data Server Driver for JDBC and SQLJ for details about the differences between those drivers.

CLI applications, Db2 CLP interface, and .Net Data Provider clients support Secure Sockets Layer (SSL). The IBM Global Security Kit (GSKit) provides encryption services for the Secure Sockets Layer (SSL) support. Refer to Configuring Secure Sockets Layer (SSL) support in non-Java Db2 clients for details about how to enable SSL in a client including how to download and install the GSKit.

Db2 APIs and Db2 commands
Review the following topics to determine if you have applications and scripts that are impacted by changes to Db2 APIs and Db2 commands in version 11.1:
SQL statements

Review the changes to SQL statements in version 11.1 to determine if you have applications and scripts that are impacted by these changes and how to manage these changes. Introduction of new functionality such as an untyped NULL keyword in expressions and a DEFAULT keyword in procedure parameters requires that you modify your applications to adapt to these changes.

System catalog views and built-in administrative routines and views

After database upgrade to version 11.1, the system catalog views under the SYSCAT schema remain compatible with catalog views that you defined in previous releases. However, there are new columns, increases in column length, or columns with changed data types in some of the system catalog views.

SQL administrative routines include changes such as new parameters and new columns returned. Also, some routines are replaced with built-in administrative routines and views. In addition, all of the built-in table functions with names that start with SNAPSHOT_ are discontinued.

Review the following topics to determine if you have applications and scripts that are impacted by changes to system catalog views and built-in administrative routines and views:
Optimizer and query execution plans

Rebind any statically bound packages after upgrade to take advantage of optimizer improvements.

Database packages

When you upgrade a database, all packages for user applications and routines are placed into an invalid state. Packages are also placed into an invalid state if they depend on database objects that you dropped, such as tables, views, aliases, indexes, triggers, referential constraints, and table check constraints. If you drop a UDF, your package is placed into an inoperative state.

Although invalid packages are automatically rebound by the database manager the first time that an application needs to access them, rebind your database packages to control when rebinding occurs and resolve any possible issues. See the Optimizer enhancements section for additional advantages of manually rebinding your database packages.

Db2 server behavior

In general, the Db2 server behavior is compatible between releases. However, there are changes in behavior to support new functionality or improve the performance of existing functionality. Review Db2 server behavior changes to determine the impact of these behavior changes on your applications.

After upgrading your Db2 server, compare your registry variable and configuration parameter values to your values before upgrade, and change any values according to the needs of your applications.

Client connectivity support

Your applications can use pre-version 11.1 clients to access databases in version 11.1 servers. However, your applications are restricted to the functionality available for that client. Review Upgrade essentials for clients to learn details about client connectivity and to identify changes in support that can impact your Db2 clients.

Upgrade of applications from Db2 version 9.7
If you are upgrading from Db2 version 9.7 , review changes in application driver support, 32-bit and 64-bit Db2 server support, and discontinued functionality between pre-version 11.1 releases that might also impact your applications and scripts: