mysql - "Only one expression can be specified in the select list when the subquery is not introduced with EXISTS"错误

Question

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我正在尝试使以下查询正常工作:

我写了这个存储过程:

IF (@Mode='CurrentRootList') 
BEGIN
SELECT ROW_NUMBER() OVER
  (
        ORDER BY emp1.EmployeeName ASC
  )AS RowNumber 
  ,emp1.empid 
  ,emp1.EmployeeName
  ,(SELECT * FROM [Mobile_Locations] mloc where emp1.MobileID=mloc.MobileID AND mloc.LocationTime = DATEDIFF(MINUTE, mloc.LocationTime , CURRENT_TIMESTAMP)) as LocationTime
  ,emp1.ArrivalTime
  ,emp1.DeviceStatus      
 INTO #CurrentDateRootList
  FROM [EMP_Locations] emp1 join [Root] root1 ON emp1.EmployeeName = root1.EmployeeName  where (CURRENT_TIMESTAMP BETWEEN root1.StartDate AND root1.EndDate)


  SELECT @RecordCount = COUNT(*)
  FROM #CurrentDateRootList

  SELECT * FROM #CurrentDateRootList
  WHERE RowNumber BETWEEN(@PageIndex -1) * @PageSize + 1 AND(((@PageIndex -1) * @PageSize + 1) + @PageSize) - 1

  DROP TABLE #CurrentDateRootList
END

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如何解决这个错误。 请帮助我。

Answer 1

填充 LocationTime 的子查询可能返回不止一行。您应该为该子查询添加 LIMIT 1。

编辑:并确保子查询只返回一列(注意 * ..)。