Finding most common values in each column

问题

Below is what I have in table myTable.

+--------+--------+--------+--------+
| value1 | value2 | value3 | value4 |
+--------+--------+--------+--------+
|   9    |   4    |   3    |   3    |
|   1    |   2    |   9    |   3    |
|   1    |   2    |   3    |   4    |
|   1    |   2    |   3    |   4    |
+--------+--------+--------+--------+

I want output as

+--------+--------+--------+--------+
| value1 | value2 | value3 | value4 |
+--------+--------+--------+--------+
|   1    |   2    |   3    |   4    |
+--------+--------+--------+--------+

value1=1 because 1 is thrice in that column.

value2=2 because 2 is thrice in that column.

value3=3 because 3 is thrice in that column.

value4=4 because 4 is twice in that column and that is maximum number of all common number in that column.

NOTE : value4 has most common values as 3 and 4. In output I should get 4 as 4 is the greatest in 3,4.

Can I achieve this in mysql?

Update 1

Table at SQL Fiddle

Update 2

I am listing answer here also so that no need to go on js-fiddle. (as per @ypercube answer)

SELECT
  ( SELECT value1
    FROM myTable
    GROUP BY value1
    ORDER BY COUNT(*) DESC
           , value1 DESC
    LIMIT 1
  ) AS value1,

  ( SELECT value2
    FROM myTable
    GROUP BY value2
    ORDER BY COUNT(*) DESC
           , value2 DESC
    LIMIT 1
  ) AS value2,

  ( SELECT value3
    FROM myTable
    GROUP BY value3
    ORDER BY COUNT(*) DESC
           , value3 DESC
    LIMIT 1
  ) AS value3,

  ( SELECT value4
    FROM myTable
    GROUP BY value4
    ORDER BY COUNT(*) DESC
           , value4 DESC
    LIMIT 1
  ) AS value4
;

回答1:

SELECT
  ( SELECT value1
    FROM myTable
    GROUP BY value1
    ORDER BY COUNT(*) DESC
           , value1 DESC
    LIMIT 1
  ) AS value1,

  ( SELECT value2
    FROM myTable
    GROUP BY value2
    ORDER BY COUNT(*) DESC
           , value2 DESC
    LIMIT 1
  ) AS value2,
...
  ( SELECT valueN
    FROM myTable
    GROUP BY valueN
    ORDER BY COUNT(*) DESC
           , valueN DESC
    LIMIT 1
  ) AS valueN
;

SQL-Fiddle: test-2

回答2:

This probably is not an ideal way to store data.
You might want to consider to use key-value pair to normalise 4 columns.
(that's mean one row for each column)

(You can use UNION to achieve what you are looking for)

(select value1, null, null, null from TABLE group by value1 order by count(*) desc, value1 desc limit 1)
union
(select null, value2, null, null from TABLE group by value2 order by count(*) desc, value2 desc limit 1)
union
(select null, null, value3, null from TABLE group by value3 order by count(*) desc, value3 desc limit 1)
union
(select null, null, null, value4 from TABLE group by value4 order by count(*) desc, value4 desc limit 1)

来源：https://stackoverflow.com/questions/10815268/finding-most-common-values-in-each-column

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