Select Code to Download

  15-dec-2000     15-jan-2001   - wider then database
  15-dec-2000     04-jan-2001   - overlaps but not contained within
  04-jan-2001     15-jan-2001   - overlaps but not contained within
  02-jan-2001     04-jan-2001   - overlaps and contained within

select *
  from t
...
       OR c_ending between p_beginning and p_ending         -- rule 2
       OR ( c_beginning < p_beginning and p_ending < c_ending ) );  --
+ rule 3

.............................................
             CB                CE
...
PB  PE                                        -- no hit
                                        PB PE -- no hit