Selects one of three optimzation controls: DEFAULT (as used by
    previous versions of Rdb), AGGRESSIVE (assumes smaller numbers of
    rows will be selected), and SAMPLED (which uses literals in the
    query to perform preliminary estimation on indices).

    The following example shows how to use this clause.

    SQL> select * from employees where employee_id  > '00200'
    cont>   optimize with sampled selectivity;