This document describes why Open Database Connectivity (ODBC) client application doesn't work with Cisco Information Server (CIS) ODBC driver until COMPOSITE_DSN_XML variable is set.
As CIS comes with an ODBC driver. If you are using an ODBC client (e.g. WinSQL), your client can use the driver to connect to a CIS server and subsequently access published resources.
Why would ODBC client application doesn't work with the CIS ODBC driver until COMPOSITE_DSN_XML variable is set?
The CIS ODBC driver has a dependency on the compositeNN.xml file (NN is the version number). This file is located under the $COMPOSITE_HOME directory by default. The ODBC driver relies on the COMPOSITE_DSN_XML variable to find the file.