Question

I need the TOP 1 string from 2 columns, the value should be returned ordered by number of appearances and by name descending. This is in SQL-Server.

Here’s an example table:

------------------------------
|   Column1    |   Column2   |
------------------------------
|     John     |   Michael   |
------------------------------
|    Thomas    |    John     |
------------------------------
|    Martin    |    Rick     |
------------------------------
|    David     |   Thomas    |
------------------------------
|     John     |   Martin    |
------------------------------

What the resulting order should look like:

----------------------------
|   Column1    |   COUNT   |
----------------------------
|     John     |     3     |
----------------------------
|    Martin    |     2     |
----------------------------
|    Thomas    |     2     |
----------------------------
|     David    |     1     |
----------------------------
|    Michael   |     1     |
----------------------------
|     Rick     |     1     |
----------------------------

What the result should look like:

----------------------------
|   Column1    |   COUNT   |
----------------------------
|     John     |     3     |
----------------------------

Answer 1

select top 1 c, count(*) [Count]
from
(
   select column1 c
     from ATable
   union all
   select column2
     from ATable
) a
group by c
order by count(*) desc

To get most used name and choose alphabetically first among them:

select top 1 c, count(*) [Count]
from
(
   select column1 c
     from ATable
   union all
   select column2
     from ATable
) a
group by c
order by count(*) desc, c

If you want to do the same but with one column only:

select top 1 column1, count(*) [Count]
  from ATable
group by column1
order by count(*) desc, column1