Converting varchar2 to Date and time

Hi Al,,

i am pulling data from oracle in CR 2008.

My question is  i have datatype of  varchar 2 in DB and contains text, null and date in format as  as 10-APR-2005 06:40:00. and i have changed date in crystal report date format same to database .  now i am taking only date by using where clause sample_id= "Date Recieved" clause , it works in toad but when i keep it in crystal report it is showing a error "A non numeric character was found where numeric was expected". My paramter in crystal report is in Date and Time field my Db Field is of type varchar 2

select a.sample_id,a.name, a.text_value from naiv_sample_attributes a inner join

nai_samples s on s.sample_id=a.sample_id where a.name='Date Received'  and

a.text_value between {?Start Date} and {?End Date}