Hi Kevin,

I will write some validation of the record entered by the user b4 saving. For example I want to
check a unique combination of fields for the record (candidate key). Should I do this in the
borules.vb? I have tried doing the below from the example given in the help
(inserting at the bottom of borules.vb):

Public Function ValidateLveRecord(ByVal tclvrnoee As String, _
       ByVal tclvrcdleave As String, ByVal tdlvrleave As Nullable(Of DateTime)) As String
       Dim message As String = Nothing
       Dim dao As mmDataAccessBase = DirectCast(Me.HostObject, _
		mmBusinessObject).GetDataAccessObject()
       Dim Connection As IDbConnection
       Dim Reader As IDataReader = dao.ExecReader _
           ("SELECT * FROM vxlves WHERE clvrnoee=@tclvrnoee AND clvrcdleave=@tclvrcdleave AND " & _
           "dlvrleave=@tdlvrleave", Connection, New IDbDataParameter() _
           {dao.CreateParameter("@tclvrnoee", tclvrnoee), dao.CreateParameter("@tclvrcdleave", _ 
	   tclvrcdleave), dao.CreateParameter("@tdlvrleave", tdlvrleave)})
        If Reader.Read() Then
           message = "(Employee# + Leave Type + Date From) must be unique"
           If Not (Me.DataSet Is Nothing) Then
               Me.AddErrorProviderBrokenRule("CustomerID", message)
           End If
       End If
       Reader.Close()
       Return message
End Function

I have got a warning in that the "Variable 'Connection' is passed by reference before it has been
assigned a value. A null reference exception could result at runtime."

My questions:

1. Am I doing at the right place?
2. If yes, how do I suppress the warning message?
3. For the line "Me.AddErrorProviderBrokenRule("CustomerID", message)", what should I put as the
first parameter to replace CustomerID since this is a combination of fields?

Thanks in advance.