Question

我是SQL和子查询的新手，当我自己运行子查询时，我得到了正确的数据输出。但是，当我运行完整查询时，我收到错误消息

SELECT *第3行的错误：ORA-00936：缺少表达式

这是我的代码：

func myLogger(message: UnsafePointer<Int8>, _ length: UInt32, _ withSysLogBanner: ObjCBool) -> Void {
    print(String(format:"myLogger: %s", message))
}

_NSSetLogCStringFunction(myLogger) // Set NSLog hook.
NSLog("foo")
_NSSetLogCStringFunction(nil) // Reset to default.
NSLog("bar")

解决方案：

SELECT 
MAX(
    SELECT 
    SUM(
        ALLOCATION.HourlyRate 
        * 
        ACTION.HrsWorked
        ) 
    FROM ALLOCATION 
    INNER JOIN ACTION 
    ON ((ACTION.ActId  = ALLOCATION.ActId) AND (ACTION.EmpId  = ALLOCATION.EmpId)) 
    GROUP BY (ALLOCATION.ActId)
)
FROM ALLOCATION
GROUP BY (ALLOCATION.ActId)

Answer 1

你需要两个括号：）

  SELECT MAX ( (  SELECT SUM (ALLOCATION.HourlyRate * ACTION.HrsWorked)
                    FROM ALLOCATION INNER JOIN ACTION ON (ACTION.ActId = ALLOCATION.ActId) AND (ACTION.EmpId = ALLOCATION.EmpId)
                GROUP BY (ALLOCATION.ActId)))
    FROM ALLOCATION
GROUP BY ALLOCATION.ActId

Select into MAX必须处于paranthesis状态。

逻辑不明确。这可以为您提供每项活动的总薪酬：

  SELECT ALLOCATION.ActId, SUM (ALLOCATION.HourlyRate * ACTION.HrsWorked) total_pay
    FROM ALLOCATION b INNER JOIN ACTION ON ACTION.ActId = ALLOCATION.ActId AND ACTION.EmpId = ALLOCATION.EmpId
GROUP BY ALLOCATION.ActId

如果您想查看哪个活动付款最多，请按desc订购：

  SELECT *
    FROM (  SELECT ALLOCATION.ActId, SUM (ALLOCATION.HourlyRate * ACTION.HrsWorked) total_pay
              FROM ALLOCATION b INNER JOIN ACTION ON ACTION.ActId = ALLOCATION.ActId AND ACTION.EmpId = ALLOCATION.EmpId
          GROUP BY ALLOCATION.ActId)
ORDER BY total_pay DESC

Select SQL中缺少表达式

1 个答案: