访问dlookup多个条件返回布尔值和订单类型不等于

Question

Private Function AllowPurge(FileID As String) As Boolean
Dim result As Boolean
Dim i As Integer

i = DLookup("COUNT(*)", "OrderMaster", "OrderStatus='S' AND FileID=" & FileID, "AND OrderType='E'")
If i > 0 Then
    result = False
Else
    result = True
End If

AllowPurge = result
End Function

OrderStatus is either marked as shipped or open 'S' or 'O'.

I need to:

• Allow purge - if every single order, other than E orders, are still open.
• Don't allow purge - if any order, other than an E order, is marked as shipped.

Answer 1

DLookup is for looking up an individual value.

DCount is for counting.

Try this one out:

Function AllowPurge(FileID As String) As Boolean

    AllowPurge = (0 = DCount("FileID", "OrderMaster", "OrderStatus='S' _
        AND FileID='" & FileID "' AND OrderType='E'"))

Exit Function

(assuming the table is called OrderMaster )

You were pretty close, except missing single quotes around the string, and missing a space, and had an extra comma.

The logic would have worked your way the same, this is just an alternate (shorter) form.

_{Thanks Lee Mac!}

Answer 2

Based on your stated logic:

I need to:

• Allow purge - if every single order, other than E orders, are still open.
• Don't allow purge - if any order, other than an E order, is marked as shipped.

I would suggest the following:

Function AllowPurge(FileID As String) As Boolean
    AllowPurge = IsNull(DLookup("FileID", "OrderMaster", "OrderStatus='S' AND FileID='" & FileID & "' AND OrderType<>'E'"))
End Function

Here, the function will only return True if every non-E-Order ( OrderType<>'E' ) is marked as Shipped ( OrderStatus='S' ).

Your current code seems to be testing for 'E-Orders' which have been shipped, and not checking whether every non-E-Order is open.

Answer 3

Thanks for the response

I tried this and seems to be working:

i = DLookup("COUNT(*)", "OrderMaster", "OrderType'E' AND OrderStatus='S' AND FileID=" & FileID)