Const ODBC_ADD_DSN = 1; // Add a new user data source. ODBC_CONFIG_DSN = 2; // Configure (modify) an existing user data source. ODBC_REMOVE_DSN = 3; // Remove an existing user data source. ODBC_ADD_SYS_DSN = 4; // Add a new system data source. ODBC_CONFIG_SYS_DSN = 5; // Modify an existing system data source. ODBC_REMOVE_SYS_DSN = 6; // Remove an existing system data source.