Get the blocking sessions

select s1.username || ‘@’ || s1.machine     || ‘ ( SID=’ || s1.sid || ‘ )  is blocking ‘     || s2.username || ‘@’ || s2.machine || ‘ ( SID=’ || s2.sid || ‘ ) ‘ AS blocking_status     from v$lock l1, v$session s1, v$lock l2, v$session s2     where s1.sid=l1.sid and s2.sid=l2.sid     and…