计算 DISTINCT 值的出现次数

Question

I am trying to find a MySQL query that will find DISTINCT values in a particular field, count the number of occurrences of that value and then order the results by the count.

example db

id         name
-----      ------
1          Mark
2          Mike
3          Paul
4          Mike
5          Mike
6          John
7          Mark

expected result

name       count
-----      -----
Mike       3
Mark       2
Paul       1
John       1

Answer 1

SELECT name,COUNT(*) as count 
FROM tablename 
GROUP BY name 
ORDER BY count DESC;

Answer 2

What about something like this:

SELECT
  name,
  count(*) AS num
FROM
  your_table
GROUP BY
  name
ORDER BY
  count(*)
  DESC

You are selecting the name and the number of times it appears, but grouping by name so each name is selected only once.

Finally, you order by the number of times in DESCending order, to have the most frequently appearing users come first.

Answer 3

Just changed Amber's COUNT(*) to COUNT(1) for the better performance.

SELECT name, COUNT(1) as count 
FROM tablename 
GROUP BY name 
ORDER BY count DESC;

Answer 4

I am trying to find a MySQL query that will find DISTINCT values in a particular field, count the number of occurrences of that value and then order the results by the count.

example db

id         name
-----      ------
1          Mark
2          Mike
3          Paul
4          Mike
5          Mike
6          John
7          Mark

expected result

name       count
-----      -----
Mike       3
Mark       2
Paul       1
John       1