Question

delete from Rentals
where (select datediff(day, OrderDate, actualReturnDate) 
       from Orders 
       inner join rentals on Orders.orderNumber = Rentals.orderNumber) > 60

我遇到错误

子查询返回了多个值

Answer 1

查询中的子查询返回多个值，如果将它们与单个值进行比较则不允许这样做。

我怀疑您只是在以错误的方式编写删除语句。您要实现的目标很薄弱。

我会猜测你打算写什么：

delete Rentals 
from Orders 
     INNER JOIN rentals ON Orders.orderNumber=Rentals.orderNumber
where DATEDIFF(day, OrderDate, actualReturnDate)>60

这将删除rentals和orderdate之间的差，其中与租赁相关的订单的行大于{60}。

请注意，由于您在编写像这样的琐碎查询时遇到问题，因此最好先读一本好书或任何可以教您编写T-SQL查询基础知识的书籍。

Answer 2

您可以尝试以下操作：

delete from Rentals
where Rentals.ID in (select rentals.ID
       from Orders 
       inner join rentals on Orders.orderNumber = Rentals.orderNumber
       datediff(day, OrderDate, actualReturnDate) > 60)

在“ WHERE”之后，Sql比较字段中的值（在这种情况下，字段=列），而不是值的集合

Answer 3

该部分查询无效：

Option Explicit
Sub CopySheets()

    Dim path As String
    Dim FileName As String
    Dim whichSheet As String
    Dim SheetNames As String
    Dim wb As Workbook

    path = GetFolder
    If path = vbNullString Then
        MsgBox "No folder was selected. Ending the procedure."
        End
    End If
    FileName = Dir(path & "*.xlsx")
    whichSheet = InputBox("Which month would you like to copy? Enter month (eg. Jan, Feb, Mar)")

    Do While FileName <> ""
        Set wb = Workbooks.Open(FileName:=path & FileName, ReadOnly:=True)
        On Error Resume Next
        If Len(wb.Sheets(whichSheet).Name) = 0 Then 'Here we handle an error on the inputname for the sheet.
        On Error GoTo 0
            SheetNames = GetSheetNames(wb)
            MsgBox "The input sheet does not exist in this workbook. The current worksheet names are: " & SheetNames
            whichSheet = InputBox("Which month would you like to copy? Enter month (eg. Jan, Feb, Mar)")
        End If
        With wb.Sheets(whichSheet)
            .Copy after:=ThisWorkbook.Sheets(1)
            .Close
        End With
        ThisWorkbook.Sheets(2).Name = Left(FileName, Application.WorksheetFunction.Search(" ", FileName) - 1)
        FileName = Dir()
    Loop

End Sub
Function GetFolder() As String
    Dim fldr As FileDialog
    Dim sItem As String
    Set fldr = Application.FileDialog(msoFileDialogFolderPicker)
    With fldr
        .Title = "Selecciona una carpeta"
        .AllowMultiSelect = False
        .InitialFileName = Application.DefaultFilePath
        If .Show <> -1 Then GoTo NextCode
        sItem = .SelectedItems(1)
    End With
NextCode:
    GetFolder = sItem
    Set fldr = Nothing

End Function
Function GetSheetNames(wb As Workbook) As String

    Dim ws As Worksheet

    For Each ws In wb.Worksheets
        GetSheetNames = GetSheetNames & ", " & ws.Name
    Next ws

End Function

那是因为select语句返回多个行，并且SQL引擎无法识别应该将datediff与60进行比较，即两者都比较？只有第一个？ in或in和...？尚不清楚，这就是SQL引擎抱怨的原因。您可以在子查询中包含过滤器，也可以将查询重写为TT。做到了。

子查询使用datediff在删除语句中返回多个值

3 个答案: