Question

我有这个代码，它总结了员工的工作时间，并使用汇总来获得总时数：

SELECT IFNULL(users, 'Total') AS Employee, 
SUM(actual) AS Amount

FROM table1

WHERE name = "ProjectName"

GROUP BY users
WITH ROLLUP

Employee  |  Amount
    A     |   15
    B     |   10
    C     |   10
  Total   |   35

我想为第三列（百分比）做的是将总和（实际）除以总计的值以获得百分比。但对于那个百分比专栏，我不需要获得总百分比。

总值不会恒定到35。

Employee  |  Amount | Percent
    A     |   15    |  42.85
    B     |   10    |  28.57
    C     |   10    |  28.57
  Total   |   35    |

我该怎么做？这是sqlfiddle：http://sqlfiddle.com/#!2/4543b/5

Answer 1

这可以按照需要运行：

SET @project_name = 'ProjectName';

SELECT IFNULL(users, 'Total') AS Employee, SUM(actual) AS Amount,
    IF(ISNULL(users), '', TRUNCATE(SUM(actual) / sum_table.amount_sum * 100, 2)
    ) AS Percent
    FROM Table1
    INNER JOIN (
        SELECT SUM(actual) AS amount_sum
            FROM Table1
            WHERE name = @project_name
    ) AS sum_table
    WHERE name = @project_name
    GROUP BY users
    WITH ROLLUP;

DEMO @ SQL Fiddle

Answer 2

也许最好的工作留给你的应用程序的逻辑层，但如果你绝对必须在数据层中这样做，那么你只需要将查询与另一个查找整体总数的查询一起加入：

SELECT   IFNULL(users, 'Total') AS Employee,
         SUM(actual) AS Amount,
         SUM(actual)/t.Total AS Percent
FROM     Table1, (
           SELECT SUM(actual) AS Total
           FROM   Table1
           WHERE  name = 'ProjectName'
         ) t
WHERE    name = 'ProjectName'
GROUP BY users WITH ROLLUP

Answer 3

SELECT if(users is NULL,'Total',users) as Employee, sum(actual) as Amount,
(CASE 
WHEN users is not null THEN CAST(sum(actual)/sum.sumAmt * 100 as DECIMAL(10,2)) 
END) as Percent

FROM Table1, (SELECT sum(actual) as sumAmt FROM Table1
              WHERE name = 'ProjectName') sum

WHERE name = "ProjectName"

GROUP BY users
WITH ROLLUP

<强> DEMO

除以汇总值

3 个答案: