Disconnection of Sessions
To disconnect from the current session, the application issues the DISCONNECT statement. To disconnect a session other than the current session, specify the numeric session identifier or connection name. To disconnect all connected sessions, issue the DISCONNECT ALL statement. For details, see Disconnect in the chapter “SQL Statements.”
After an application disconnects from the current session in a multi-session application, the application must establish the current session by issuing the SET CONNECTION, SET_SQL(SESSION), or CONNECT statement. If no current session is in effect when an application issues a query, an error is returned.