How to group by ID, and output without repeating IDs? Input 

UserID  Profile
101     apple
102     banana
103     pie
101     banana
102     pine
103     berry


Output

UserID  Profile
101     apple
        banana
102     banana
        pine
103     pie
        berry
This problem will by solved by group by function.

Whatever tool you are using (R or SQL), you need to just group the data by UserID.