This is a JDBC-ODBC bridge. The DSN contains information about the database that the ODBC driver needs to connect to. The DSN would contain information like databaseName, userName and password along with other details and may be secure in certain cases allowing only a single user to access the database. Instead of specifying all these details like userName, password, driverName and others as properties, a DSN is specified as a databaseName property.
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