count statement needed

hello experts,

i have a table like the one below
i need to know for each  code how many different tours are existing.

code  name    tour
100    peter     4
100    peter     4
100    peter     4
330    peer      3
330    peer      3
330    peer      2

the statement should give me this information
100 --> 1 because only one tour
330 --> 2 because two differnt entries

thanks a lot