Select in each response different values with Mysql Database

Question

I would like to know how to select the number of records from a table where only values greater than 6 are selected, but each result is different, with the Mysql database, for example:

Tabela Notas
Unidade I    |  Unidade II    |  Unidade III   | Unidade IV
10           |  4             |  7             | 3
1            |  3             |  7             | 9
7            |  0             |  8             | 1

Where values greater than 6 will appear like this in the query;

Unidade I    |  Unidade II    |  Unidade III   | Unidade IV
2 Registros  |  0 Registros   |  3 Registros   | 1 Registro

Answer 1

Functional code:

select
count(case when `Unidade I` > 6 then 0 end) as 'Unidade I',
count(case when `Unidade II` > 6 then 0 end) as 'Unidade II',
count(case when `Unidade III` > 6 then 0 end) as 'Unidade III',
count(case when `Unidade IV` > 6 then 0 end) as 'Unidade IV'
from Notas

Note that case the field name in the existing table space, is due referencing it among stars "`".

Answer 2

I managed to solve this problem, is as below

SELECT 
COUNT(CASE WHEN nota_valorI>6 then 1 ELSE NULL END) as "UNI_I",
COUNT(CASE WHEN nota_valorII>6 then 1 ELSE NULL END) as "UNI_II",
COUNT(CASE WHEN nota_valorIII>6 then 1 ELSE NULL END) as "UNI_III",
COUNT(CASE WHEN nota_valorIV>6 then 1 ELSE NULL END) as "UNI_IV"
from nota

Answer 3

SELECT * FROM
(

SELECT `Unidade I` AS UN FROM NOTAS
UNION 
SELECT `Unidade II` AS UN  FROM NOTAS
UNION
SELECT `Unidade III`AS UN  FROM NOTAS
UNION
SELECT `Unidade IV` AS UN  FROM NOTAS
) AS TA

WHERE UN  > 6