sdt_cod     result
======    =====
 101 	P
 102	P
 103	F
 103 	P
 104  	F
 104	P
 105	F
 105	F
 105	P
 106	F
 106	F
 106	P.
 107	F
 107	F
 107	P.
P - Pass 
F- Fail

here 102 & 102 are passed in first attempt..
103 & 104 are passed in 2nd attempt
105, 106 & 107 are passed in 3rd attempt

I WANT THE RESULT AS
count(sdt_code)  test attempt
     2                           1
     2                            2
     3                           3