SubQuery in SQL Statement

When I run the code below, I get an exception "Specified cast is not valid."

   Dim strSQL As String
   Dim dreader As OleDb.OleDbDataReader
      strSQL = "... some SQL query ..."
      dreader = AccessDBIneraction.GetDataAsDataReader(strSQL)
      While dreader.Read()
         If dreader.GetString(2) = "F" OrElse IsNumeric(dreader.GetString(2)) Then
            strSQL = "... some other SQL query ..."
         End If
      End While
   Catch ex As Exception
      If Not (dreader Is Nothing) Then
         If Not dreader.IsClosed Then
         End If
      End If
   End Try
<code removed per request http:Q_21903646.html>
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Éric MoreauSenior .Net ConsultantCommented:
Hi GivenRandy,

on which line ?

GivenRandyAuthor Commented:
On this line:

         If dreader.GetString(2) = "F" OrElse IsNumeric(dreader.GetString(2)) Then

In Access, BatesMain and BatesRange are type Number, while NewNumber is type Text.
Éric MoreauSenior .Net ConsultantCommented:
i can't see. place a breakpoint on the line and check the value of dreader.GetString(2). It could be a NULL.

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GivenRandyAuthor Commented:
Indeed, it was null. Duh!
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