Display duplicated data in the list
===

Goal:   
Display the duplicated data, in table testing, that shall be deleted.  
However,
If there are two duplicated data that is for instance "3412 New York". 1 row only should be displayed in the testing table.

Problem:  
Don't know how to do it.
Please keep in mind that this table can be a million of row.


    All data from the list
    
    table testing
    Region          Category    Energy
    ----------------------------------
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3412 New York   food        3
    3412 New York   food        3
    3412 Washington coke        7
    3412 california chips       20
    3412 california chips       20
    3412 california chips       20
    3412 california chips       20
    
    
    
    
    
    Requested result that should display data in table testing
    Table testing
    Region          Category    Energy
    ----------------------------------
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    1235 Delaware   candy       5
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3125 New Jersey drink       4
    3412 New York   food        3
    3412 california chips       20
    3412 california chips       20
    3412 california chips       20

