Paresh, I remember v$tempseg_usage (i.e. v$sort_usage) records the previous SQL. I found my old study note that says "the two SQL columns (sqladdr and sqlhash) in v$sort_usage record the SQL that *last* ran using temporary segment. If the SQL is currently running consuming temp space, you have to find it in v$session sql_address and sql_hash_value. V$session.prev_sql_addr and prev_hash_value are exactly the same as v$sort_usage.sqladdr and sqlhash, respectively." So if you want to join, it's prev_sql_id that matches sql_id of v$tempseg_usage. Yong Huang -----Original Message----- You are right Alex. Thanks for your help. When I use session_address to figure out sql_id from v$session and v$tempseg_usage views, both show different SQL_IDs. Here is the query I used, select a.session_addr,b.saddr,a.sql_id sqlid_tempseg ,b.sql_id sqlid_session,sid from V$TEMPSEG_USAGE a, v$session b WHERE a.session_addr= b.saddr; If I take sql_id which v$session shows and check in v$sql, it shows the sql which populate this global temporary table, which is correct but sql_id which v$tempseg_usage has, shows different sql in v$sql. Does anyone have any idea why both views show different sql_id? Thanks, Paresh Patel, -- //www.freelists.org/webpage/oracle-l