Hi Folks We have a report query with bind variables. This query has 20 sql_childs. when we use literals which are taken from the sql_bind_capture view the query uses the optimal plan.I have invalidated the plan which was using the child 18 with a simple ddl operation. but CBO start to use the wrong plan of the child 20 (we tried its literals too and explain plan output gives the right plan). Why doesn't CBO create a new right plan for me as a child 21 instead of using a stored wrong one when i invalidate the plan ??? I hope i am clear with the situation Thanks -- A. Coskan GUNDOGAR Oracle DBA http://coskan.wordpress.com