Some test can be built like below. Begin For I in (select * from v$session ) loop dbms_lock.sleep(...); --- Fetch data, do something end loop; ============================== Regards. Serol Luo, From Peking,China Or call me RollingPig http://rollingpig.itpub.net -----????----- ???: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx]?? amonte ????: 2006?9?5? 6:14 ???: oracle-l@xxxxxxxxxxxxx ??: [SPAM] dynamic views cosnstency, do they use UNDO? ???: ? Hi Since v$ views based on x$ are memry structures I guess there is no guarantee that they would give a consistent view correct? For example in some busy systems, for example a 2500 users CRM system running joins of v$ views is time consuming, for example if I try to join v$sesstat with v$session it takes really a while. If let's say it takes 10 seconds does Oracle guarantee the values I am seeing are from 10 seconds ago? I am pretty sure undo is not used for memory structures or wrong? I Cant seem to find a easy way to test this. TIA Alex