Έλεγχος εγγραφών εάν είναι null

[thanoswsi]

Εχω κάνει την παρακάτω function αλλα δεν μου βγάζει null οταν οι εγγραφές που εισάγω απο αρχείο excel. Μπορείτε να δείτε τι δεν πάει καλά

Sub CreateErrStr(FldName As String)
    Dim rst As DAO.Recordset
    Dim StrSql As String
    Dim strFld As String
    Dim ErrStr As String
    strFld = FldName
    'StrSql = "SELECT Thanos.*, Thanos.EmplID FROM Thanos WHERE (((Thanos. " & FldName & ") Is Null));" 
    StrSql = "SELECT Thanos.*, Thanos.EmplID, Thanos.Surname, Thanos.FirstName, Thanos.Vat  
FROM Thanos WHERE (((Thanos.EmplID) Is Null) or 
((Thanos.Surname) Is Null) or ((Thanos.FirstName) Is Null) or ((Thanos.Vat) Is Null));"

    Set rst = Application.CurrentDb.OpenRecordset(StrSql)
    If rst.RecordCount = 0 Then
        rst.Close
        Exit Sub
    End If
    rst.MoveFirst
    Do
        ErrStr = " To Pedio " & rst(FldName) & " exei timi " & Nz(rst(strFld), "Null")
        rst.Edit
        If Nz(rst!ErrStr, "") = "" Then
                rst(ErrStr) = ErrStr
        Else
                rst(ErrStr) = rst(ErrStr) & "ÊÁÉ" & ErrStr
        End If
        rst.Update
        rst.MoveNext
        If rst.EOF Then Exit Do
    Loop
    rst.Close
End Sub

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