mysql - 尝试合并表时出现访问错误
问题描述
对不起,如果它真的很简单,我是新手。我一直在尝试合并两张桌子,但无法完成。试图将员工人数添加到另一个表。
SELECT [Training History].JobID,
(
SELECT Job.Department
FROM Job
WHERE [Training History].JobID = Job.JobID) AS Department,
SUM([Expenditure]) AS ExpenditureOfJob
FROM [Training History]
GROUP BY [Training History].JobID,
(
SELECT [Number of Employees]
FROM Q9r,
WHERE Q9r.JobID = [Training History].JobID
)
;
这在最后一个选择语句中给了我一个错误,请帮助:)
Q9r 表代码为;
SELECT JobID, COUNT (*) AS [Number of Employees] FROM Employee GROUP BY JobID;
enter code here
也不能让它工作(这是我更喜欢的方式,因为它可以在一个表中完成)
SELECT [Training History].JobID,(
SELECT Job.Department
FROM Job
WHERE [Training History].JobID = Job.JobID)
AS Department,
SUM([Expenditure]) AS ExpenditureOfJob
FROM [Training History]
GROUP BY [Training History].JobID,
(SELECT COUNT (*) AS [Number of Employees]
FROM Employee
GROUP BY JobID)
;
这也不起作用
SELECT [Training History].JobID,(SELECT Job.Department FROM Job WHERE [Training History].JobID = Job.JobID) AS Department,
SUM([Expenditure]) AS ExpenditureOfJob FROM [Training History] GROUP BY [Training History].JobID,
(SELECT COUNT (*) AS [Number of Employees]
FROM Employee
WHERE [Training History].JobID = Employee.JobID
GROUP BY JobID)
;
解决方案
您可以通过这种方式轻松组合 2 张表格:
-- My way to combinates 2 tables:
SELECT Department.JobID, Department.NameDepartment,
Department.ExpenditureOfJob, Job.NumberOfEmployees
FROM Department INNER JOIN Job
ON Department.JobID = Job.JobID
GROUP BY Department.JobID;
顺便说一句,您的查询可以适应这种形式:
-- I suppose that the Training History & Expenditure both are the Databases_Name...
SELECT [Training History].JobID, Job.Department AS Department, SUM([Expenditure]) AS ExpenditureOfJob
FROM [Training History].Department INNER JOIN [Training History].JobID
GROUP BY [Training History].JobID,( SELECT COUNT (*) AS [Number of Employees]
FROM Employee
GROUP BY JobID);
无论如何,我将测试留在SQL Fiddle
推荐阅读
- postgresql - 创建分区时已存在 PostreSQL 错误关系
- php - 使用 AbstractNormalizer::ATTRIBUTES 规范化嵌套对象
- ruby-on-rails - Docker Web 映像现在可以与 rspec gem 一起使用
- python - 在 TensorFlow Hub 模型上使用 TensorBoard 时出现 InvalidArgumentError
- android - 每次在带有导航的底部导航视图中选择一个选项卡时,都会创建片段的新实例
- reactjs - React Router - 在变量或组件中分组路由
- java - 如何避免多次空检查,如果需要在每次检查后做一些事情
- swift - 为什么从不调用 DispatchGroup deinit?
- java - 已解析的 Groovy 脚本的(反)序列化
- apache-nifi - 有没有办法以编程方式接收 NiFi 远程进程组的目标 uri?