Hi: Everyone When I monitoring the system I found some sessions cause the wait_event --------- i/o slave wait in a few seconds and I found the sql_id of these sessions is 38wm92jbxu0vf,but when I query v$sql I found the sql_text is null who can explain these? and I guess this query is on a table with clob column. -- //www.freelists.org/webpage/oracle-l