mysql 查询中的总和值

Question

mysql 查询如下:

SELECT count(f.id) as total, m1.fname FROM members m1 INNER JOIN new f ON m1.id = f.id

该查询的结果:

   total | fname  | 
  ------------------
    2    |  john
    3    |  mike
    5    |  july

如何使用此 mysql 查询对“total”列中的值求和？

Answer 1

在子查询上使用SUM:

SELECT SUM(c.total) AS total_sum
FROM (
    SELECT count(f.id) as total, m1.fname
    FROM
        members m1 INNER JOIN
        new f ON m1.id = f.id
) AS c