How to remove duplicate data from hbase

Question

I have a hbase table.

Table Schema: empid, empname,age

Data 1: Key - 1001 Value- 1,John,26 (Correct Data)

Data 2: Key - 1002 Value- 1,John,25 (InCorrect Data. By Mistakely entered by user.)

There is only two column has same values which empid, empname. I want to fetch those records which has same value for all column except single column value is different.

Note: It can be possible 3 column has same value but fourth one has different.

It would be good if you can give me Impala Query.