Connectivity requirements

You must run Db2 ODBC applications on a machine that has Db2 12 for z/OS® installed. Additional requirements also apply.

Db2 for z/OS ODBC has the following additional connectivity requirements:

If the application is executing with MULTICONTEXT=1, it can make multiple physical connections. Each connection corresponds to an independent transaction and Db2 thread.
If the application is executing CONNECT (type 1) and MULTICONTEXT=0, only one current physical connection and one transaction on that connection occurs. All transactions on logical connections (that is, with a valid connection handle) are rolled back by the application or committed by Db2 ODBC. This is a deviation from the ODBC connection model.