IBM Data Server DB2 - Manual (Page 172)

158 DB2 Deployment Guide
4.3.3 Considerations for deployment of CLI and ODBC applications
For scenarios where the IBM Data Server Client or Runtime Client has already
been installed, deploying a C/C++ application is straightforward. You only have to
install the application on the target system and then catalog locally the database
to which the application is going to connect. During runtime, application directly
reads connectivity information from the local catalog.
In this section, we discuss a different case where an application is to be deployed
to an environment without the DB2 Client. The IBM Data Server Driver for ODBC
and CLI is thus required to be deployed along with the application.
Redistributable driver files
The IBM Data Server Driver for ODBC and CLI is a freely downloable product.
There are conditions required for redistributing the IBM Data Server Driver for
ODBC and CLI with an application. We describe this in more detail in 4.1.2, “IBM
Data Server Driver for ODBC, CLI, and .NET, and IBM Data Server Driver for
ODBC and CLI” on page 143. Make sure that all the required conditions are met
prior to packaging the driver with your application for deployment.
Connecting to database
After deploying C/C++ applications that use the IBM Data Server Driver for
ODBC and CLI, some application configuration may be required depending on
the connecting method the application used. There are five ways to specify the
connectivity information if the application is working only with IBM Data Server
Driver for ODBC and CLI:
Save connectivity information in a connection string and call
SQLDriverConnect() to establish a connection. No particular application
specific configuration is required if you use this method and specify database,
host, and port in the connection string. This is the method used in our C/C++
application deployment example.
Use the CLI initialization file, db2cli.ini, to configure the connection. This
method is for CLI applications only, and db2cli.ini change is required.
Register the database as an ODBC data source with the ODBC manager.
This is required for the ODBC application only. db2cli.ini or other platform
specific configuration changes are required.
Use the FileDSN CLI/ODBC keyword to specify database connectivity
information. db2cli.ini, or other platform specific configuration changes that
are required.
For a local database only, use PROTOCOL and DB2INSTANCE CLI/ODBC
keywords to specify the local database. db2cli.ini change is required.