Amit > Can you set any parameter the way you mentioned ? No. You need a specific hint for that. For this reason in my first reply I wrote "you can set that specific parameter". In this case the hint has the name of the parameter, but it's just a "coincidence". For example for dynamic sampling the parameter is named optimizer_dynamic_sampling but the hint dynamic_sampling. > If yes than does thatn mean opt_param is not required at all ? This hint is generic and can be used to set some (but not all) parameters used by the query optimizer. Please, don't ask me to provide a list of the supported parameters. I don't have it. If you have some particular need, just try it... HTH Chris -- //www.freelists.org/webpage/oracle-l