访问日期比较不适用于特定日期

Question

我做了一个表单来更新历史数据和一个子表单，用来检查结果！除了一个小问题外，一切都很好。

Private Sub runbtn_Click()

Me.Refresh

Dim theminimum As String
Dim theprodscID As String
Dim thepurchasedate As Date

If IsNull(Me.purchasedate) = False Then

theprodscID = Str(Me.prodscID)
thepurchasedate = Me.purchasedate.Value

'minimum textbox

    theminimum = "Select Top 1 [update value]" & _
                " From [product and shareclass level data update]" & _
              " Where [product and shareclass level data update].[dataID] =" & Str(1) & _
              " And [product and shareclass level data update].[prodscID] =" & theprodscID & _
              " And ([product and shareclass level data update].[timestamp] <= #" & thepurchasedate & "#)" & _
              " Order by [product and shareclass level data update].[timestamp] DESC"


    If CurrentDb.OpenRecordset(theminimum).RecordCount = 0 Then
    Me.minimum = Null
    Else
    Me.minimum = CurrentDb.OpenRecordset(theminimum).Fields(0).Value
    End If

Answer 1

您的问题是，日期值必须正确地格式化为文本表达式。因此：

" And ([product and shareclass level data update].[timestamp] <= #" & Format(thepurchasedate, "yyyy\/mm\/dd") & "#)" & _

或者，实现我的函数CSql，或者更好的方法是开始使用参数（Bing/Google）。