Periksa perubahan di semua kolom lain berdasarkan kesamaan satu kolom

Data yang Anda inginkan pada dasarnya adalah jumlah entitas yang memiliki lebih dari satu nilai dalam satu kolom.

Ini paling mudah dihitung berdasarkan kolom:

select sum(case when NumFirstNames <> 1 then 1 else 0 end) as DifferentFirstNames,
       sum(case when NumLastNames <> 1 then 1 else 0 end) as DifferentLastNames,
       sum(case when NumSSN <> 1 then 1 else 0 end) as DifferentSSN,
       sum(case when NumPhone <> 1 then 1 else 0 end) as DifferentPhone       
from (select EncounterId, count(*) as Num,
             count(distinct FirstName) as NumFirstNames,
             count(distinct LastName) as NumLastNames,
             count(distinct SSN) as NumSSN,
             count(distinct Phone) as NumPhone
      from table t
      group by EncounterId
     ) e;

Anda dapat memformat hasil sesuka Anda.