In 10g MONITORING clause is deprecated, and if you have STATISTICS_LEVEL>BASIC all the segments are monitored. From my observations performance degradation from MONITORING segments is very low, because Oracle changes counters in memory and flushes changes periodically (asynchronously). You can search archives, this topic has been discussed here. The data that is collected during monitoring of the segment is used by the dbms_stat to determine if the segment statistics are staled and should statistics be regathered, so there will be no effect from monitoring segments with STALED statistics. Please read this thread for more information: http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:1260600445561 And of course don't forget to test your ideas before implementing them on the production servers. On 9/14/05, The Human Fly <sjaffarhussain@xxxxxxxxx> wrote: > Friends, > > We also planning to enable table monitoring on this schema to collect > statistics on table which has STALE statistics. Does this effect the > performance? > > Thank you in advance > -- > Best Regards, > Syed Jaffar Hussain > OCP 8i & 9i DBA, > Banque Saudi Fransi, > Saudi Arabia -- Best regards, Edgar Chupit callto://edgar.chupit -- //www.freelists.org/webpage/oracle-l