Who is blocking who, Oracle non-RAC

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 l1.BLOCK=1 and l2.request > 0 

and l1.id1 = l2.id1 

and l2.id2 = l2.id2 ;

BLOCKING_STATUS 

-------------------------------------------------------------------------------- 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macatl02 ( SID=91 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macatl02 ( SID=92 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@scmsnq01 ( SID=96 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macatl02 ( SID=97 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macsnq01 ( SID=98 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@stfsnq04 ( SID=99 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@scmsnq01 ( SID=100 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macatl02 ( SID=102 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@macatl02 ( SID=103 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@scmatl03 ( SID=105 ) 

MSS@stfatl03 ( SID=1064 )  is blocking MSS@stfsnq04 ( SID=106 )