Could you please comment on the following SQL queries between Original SQL and Modified SQL. It seems that modified SQL's are perfoming better but I don't know how exactly Oracle optimizer works. Original Query1: SELECT * FROM orders WHERE orders_updt_dtm BETWEEN sysdate - 7 AND sysdate / Modified Query1: SELECT * FROM orders WHERE 7 >= sysdate - orders_last_updt_dtm / Original Query2: SELECT * FROM sales WHERE sales_updt_dtm BETWEEN sysdate - 7 AND sysdate / Modified Query2: SELECT * FROM sales WHERE sales_updt_dtm >= sysdate - 7 - 0 AND sales_updt_dtm <= sysdate - 0 / Thanks, Bob ____________________________________________________________________________________ Yahoo! oneSearch: Finally, mobile search that gives answers, not web links. http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC -- //www.freelists.org/webpage/oracle-l