这个sql语法正确吗？答案

【问题标题】：Is this sql syntax correct?这个sql语法正确吗？
【发布时间】：2010-02-23 07:41:47
【问题描述】：

我可以在ISNULL() 中应用SUM().... 考虑我下面的sql server select 语句

SELECT e.Emp_Id,e.Identity_No,e.Emp_Name,case WHEN e.SalaryBasis=1 
THEN 'Weekly' ELSE 'Monthly' end as SalaryBasis,e.FixedSalary,
    ISNULL(Adv.Daily_Wage,0) as Advance from Employee as e 
    inner join Designation as d on e.Desig_Id=d.Desig_Id
    Left Outer Join Payroll as Adv on e.Emp_Id=Adv.Emp_Id where e.Is_Deleted=0

此声明工作正常....但是当我在 ISNULL() 中应用 SUM() 时

SELECT e.Emp_Id,e.Identity_No,e.Emp_Name,case WHEN e.SalaryBasis=1 
    THEN 'Weekly' ELSE 'Monthly' end as SalaryBasis,e.FixedSalary,
        ISNULL(SUM(Adv.Daily_Wage),0) as Advance from Employee as e 
        inner join Designation as d on e.Desig_Id=d.Desig_Id
        Left Outer Join Payroll as Adv on e.Emp_Id=Adv.Emp_Id 
        where e.Is_Deleted=0

我收到了错误，

列“Employee.Emp_Id”在选择列表，因为它不是包含在任一聚合中函数或 GROUP BY 子句。

任何建议....

【问题讨论】：

标签： sql-server-2005 select sum isnull

【解决方案1】：

您需要 GROUP BY 选择中的其他列。类似的东西

SELECT  e.Emp_Id,
        e.Identity_No,
        e.Emp_Name,
        case 
            WHEN e.SalaryBasis=1  THEN 'Weekly' 
            ELSE 'Monthly' 
        end as SalaryBasis,e.FixedSalary, 
        ISNULL(SUM(Adv.Daily_Wage),0) as Advance 
from    Employee as e  inner join 
        Designation as d on e.Desig_Id=d.Desig_Id Left Outer Join 
        Payroll as Adv on e.Emp_Id=Adv.Emp_Id  
where   e.Is_Deleted=0 
GROUP BY e.Emp_Id, --This section is what you are missing
        e.Identity_No,
        e.Emp_Name,
        case 
            WHEN e.SalaryBasis=1  THEN 'Weekly' 
            ELSE 'Monthly' 
        end,
    e.FixedSalary

看看这里的定义

GROUP BY (Transact-SQL)

【讨论】：

GROUP BY 中的case 感觉对我来说效率低下...你也可以用e.SalaryBasis 分组。