DBMS_SYSTEM.SET_BOOL_PARAM_IN

DBMS_SYSTEM.SET_BOOL_PARAM_IN_SESSION Procedure

This procedure sets a Boolean parameter in another session.

Argument Name	Type	In/Out	Default?
SID	NUMBER	IN
SERIAL#	NUMBER	IN
PARNAM	VARCHAR2	IN
BVAL	BINARY_INTEGER	BOOLEAN

Note that this procedure does not work for the SQL_TRACE parameter.

For example to set the HASH_JOIN_ENABLED parameter to FALSE in a session with SID 9, serial# 29 use:

EXECUTE dbms_system.set_bool_param_in_session (9, 29, 'hash_join_enabled', FALSE);

The SID and serial# for the session can be obtained from V$SESSION e.g.:

DECLARE
    l_sid NUMBER;
    l_serial NUMBER;
BEGIN
    SELECT sid, serial#
    INTO l_sid, l_serial
    FROM v$session
    WHERE username = 'User1';

    dbms_system.set_bool_param_in_session 
    (l_sid, l_serial, 'hash_join_enabled', FALSE);
END;
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