What is "exact match" for you?

a) In some column TRUE is displayed, when on same row in column A the entry has matching value in column B;
b) In some column TRUE is displayed, when on same row in column B the entry has matching value in column A;
c) Point a is applied to some column, and point b is applied applied to some another column;
d) In column A the entry is formatted differently, when it has matching value in column B;
e) In column B the entry is formatted differently, when it has matching value in column A;
f) Both points a and b are applied;
g) When on same row in column A the entry has matching value in column B, in some column the row number (or some other row indicator) where maching value was found is displayed;
... the list may go on and on!