我想写一个查询来生成员工的出勤报告。首先,我将告诉您员工的存在如何存储在我的数据库中。
我有以下表格。
Employee Table with Columns
emp_id emp_Name Joining_Date
1 john 11-01-2012
2 Scott 12-01-2012
Holiday Table
Holiday_Name Date
Chrismas 25-12-2012
Dushera 08-03-2012
Independance Day 15-08-2012
Leave Table
Subject from_Date to_Date Emp_Id status
PL 02-01-2012 04-01-2012 1 Approved
CL 11-01-2012 12-01-2012 2 Declined
Doctor Table
Subject Call_Date call_Done_By(emp_id)
Call 15-01-2012 1
CA 21-02-2012 2
Chemist Table
Subject Call_Date call_Done_By(emp_id)
Chemist 1-02-2012 2
Texo 21-03-2012 1
如果员工被医生或化学家访问,该特定日期将与employee_id一起存储在该特定医生或化学家表中
现在,人们将选择年份和月份,他应该能够以下列格式获得出勤报告 示例:假设用户选择年份为“2011”,月份为“Dec”,则输出应为
Employee year Month 1 2 3 4 5 6 7....
John 2011 Nov Y Y Y Y Y L S....
Scott 2011 Nov Y Y L M Y L S
这里输出1,2,3 ....是0-30个月的日子,我们可以使用'case'来写
考虑员工是否在当天出现,其状态为“Y”,否则为L else 如果他去了医生,化学家这样的顾客,那就换成'S'。
那么我该怎么写一个查询来实现这个输出呢? 任何建议对我都有帮助....
答案 0 :(得分:1)
这是一个应该按预期工作的漫长道路:
SELECT
Employee.emp_Name,
'2011' AS `Year`,
'Dec' AS `Month`,
CASE (
IF(
DATE('1-12-2011') < DATE(Employee.Joining_Date)),
'0' --Not joined yet
IF (
(SELECT COUNT(*) FROM Holiday WHERE DATE('1-12-2011') = DATE(Holiday.date)) = 1,
'1', --National Holiday
IF (
(SELECT COUNT(*) FROM Leave WHERE DATE('1-12-2011') > DATE(Leave.to_Date) AND DATE('1-12-2011') < DATE(Leave.from_Date) AND Leave.Emp_Id = Employee.emp_id) = 1,
'2', --On Leave
IF(
(SELECT COUNT(*) FROM Doctor WHERE DATE('1-12-2011') > DATE(Doctor.Call_Date) AND Doctor.call_Done_By = Employee.emp_id) = 1 OR
(SELECT COUNT(*) FROM Chemist WHERE DATE('1-12-2011') > DATE(Chemist.Call_Date) AND Chemist.call_Done_By = Employee.emp_id) = 1,
'3' --Visit Doctor or Chemist
'4' --Employee was at work
)
)
)
)
)
WHEN 0 THEN 'N/A' --Not joined yet
WHEN 1 THEN 'L' --National Holiday
WHEN 2 THEN 'L' --On Leave
WHEN 3 THEN 'S' --Visit Doctor or Chemist
ELSE 'Y' --Employee was at work
END AS `1`, --first day of month
... AS `2`, --repeat for second day of the month till max day of current month replace '1-12-2011' with each different day of month
...
... AS `30`
FROM
Employee
我的建议是创建一个视图,为每个员工执行if语句,使代码更容易维护。请记住,这是伪代码,可能需要一些更改才能运行。
希望这有帮助。