我想知道如何能我举个例子,如果我有:我可以根据条件将值插入到列中吗? SQL服务器
Employees: nameOfEmployee,numberOfEmployee,numberOfDepartment,....,....,....,....,...,....,....
Departments: numberOfDepartment,numberOfEmployees,....,....,....,....,...,....,....
,且已存在的表中的行,填补了值Departments.numberOfEmployees与nameOfEmployee
的加入到目前为止我唯一想到的是:
UPDATE Departments
SET numberOfEmployees=COUNT(Employees.nameOfEmployee)
FROM Employees
WHERE Departments.numberOfDepartment=Employees.numberOfDepartment
我知道这可能甚至没有任何意义。我刚开始使用SQL
你靠近;) – Youness 2014-09-05 16:00:04
你坚持汇总数据。大多数时候,你不想这样做。从Departments部门选择dept.numberOfDepartment,[MyCount] = count(*)demp.numberOfDepartment = emps.numberOfDepartment Group By dept.numberOfDepartment – granadaCoder 2014-09-05 17:18:05
我试过了,但没有奏效。我看不出COUNT实际上是如何计算员工人数的。它不是必须以某种方式与numberOfEmployees相关吗? – 2014-09-05 17:34:19