Character date to numeric date value

I have a variable CPN_DT that is char, length 80 format $80, has following value 

05/21/2010

07/01/2010

03/01/2011

How do I convert it to sas date? I used following, but it doesn't work

cpn_dt = input(trim(cpn_dt),MMDDYY10.);

How can I fix this?

I really wonder why sas read this as char type with length of 80, because I got this variable via proc sql through odbc to oracle database.

why does SAS not recognize this as a mmddyy10. value?

Well, it seems working for me, please see:

data have;

infile cards;

informat date $80.;

input date ;

cards;

05/21/2010

07/01/2010

03/01/2011

;

data want;

set have;

format _date mmddyy10.;

_date=input(trim(date),MMDDYY10.);

run;

proc sql;

  create table want1 as selectinput(substr(strip(cpn_dt),1,10),MMDDYY10.)

     as cpn_dt format mmddyy10.

        from have;

quit;

proc contents data=want1;run;