我正在尝试编写一条MySQL语句,该语句将使我返回这些结果：

## Name | Day 0 | Day 1 | Day 2 | Day 3 | Day 4 | Day 5 |
##Jeff  |   0   |    3  |     1 |     2 |    1  |   1   |
##Larry |   1   |    1  |     4 |     4 |    1  |   0   |

基于每个员工每天执行多少任务.

我的数据库表如下：

雇员

id(INT),数字(VARCHAR),名称(VARCHAR),dateStarted(VARCHAR),

项目

id(INT),数字(VARCHAR),dateEnded(DATETIME)

现在,我正在使用以下语句：

SELECT 
a.name AS "Name",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 0",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 1",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 2",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 3",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 4",
count(abs(datediff(STR_TO_DATE(a.dateStarted, '%Y-%m-%d %H:%i:%s'), b.dateEnded))) AS "Day 5"
FROM employee a, project b
WHERE b.number=a.number 
AND "Day 0" = 0
AND "Day 1" = 1
AND "Day 2" = 2
AND "Day 3" = 3
AND "Day 4" = 4
AND "Day 5" >= 5

电流输出

上面的语句有效,但是由于某种原因,它不能提供上述要求中提到的期望结果.关于如何修复/更改它的任何想法？

编辑

如果我取出：

AND "Day 0" = 0
AND "Day 1" = 1
AND "Day 2" = 2
AND "Day 3" = 3
AND "Day 4" = 4
AND "Day 5" >= 5

然后打印出来：

## Name | Day 0 | Day 1 | Day 2 | Day 3 | Day 4 | Day 5 |
##Jeff  |   9   |    9  |     9 |     9 |    9  |   9   |

解决方法:

尝试这个：

SELECT
  emp.name AS '## Name',
  (SELECT COUNT(*)     
   FROM project p JOIN employee e ON p.number = e.number
   WHERE e.name = emp.name 
     AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) = 0
   ) AS 'Day 0'
  ,(SELECT COUNT(*)
    FROM project p JOIN employee e ON p.number = e.number
    WHERE e.name = emp.name 
      AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) = 1
   ) AS 'Day 1'
  ,(SELECT COUNT(*)
    FROM project p JOIN employee e ON p.number = e.number
    WHERE e.name = emp.name 
      AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) = 2
   ) AS 'Day 2'
  ,(SELECT COUNT(*)
    FROM project p JOIN employee e ON p.number = e.number
    WHERE e.name = emp.name 
      AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) = 3
   ) AS 'Day 3'
  ,(SELECT COUNT(*)
    FROM project p JOIN employee e ON p.number = e.number
    WHERE e.name = emp.name 
      AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) = 4
   ) AS 'Day 4'
  ,(SELECT COUNT(*)
    FROM project p JOIN employee e ON p.number = e.number
    WHERE e.name = emp.name 
      AND datediff(str_to_date(p.dateEnded, '%Y-%m-%d'), e.dateStarted) >= 5
   ) AS 'Day 5'
FROM employee emp
GROUP BY emp.name

请参阅SQL Fiddle Demo(-已根据提供的信息对您的数据进行了一些假设).