i am trying to setup auto complete on 2 columns of a DataGridView populated from an sql Server 2008 r2 database. i have tested working a previous version of this code until a NULL value was passed into the database. the query worked fine as 

> 
> "SELECT DISTINCT " & Column & " FROM dbo.Purchases"
> 
> 
> 

i tested my new Query in "SQL Server Management Studio" and got the results i was expecting, the same as before minus the Null, but when i put the new query into the code i get an Exception.

> 
> System.Data.SqlClient.SqlException (0x80131904): Incorrect syntax near the keyword 'NULL'.
> 
> 
> 

```
Private Function fillACList(Column As String) As AutoCompleteStringCollection
    Dim temp As AutoCompleteStringCollection
    temp = New AutoCompleteStringCollection
    Using acConn As SqlConnection = New SqlConnection("Data Source=xxx.xxx.xxx.xxx,xxxx;Trusted_Connection=Yes;database=Purchasing_DB")
        Try
            acConn.Open()
        Catch ex As Exception
            MessageBox.Show(ex.ToString() & " FillACList")
        End Try
        Using cbCommand As SqlCommand = New SqlCommand("SELECT DISTINCT " & Column & " FROM dbo.Purchases WHERE " & Column & " IS NOT NULL", acConn)
            Dim reader As SqlDataReader = cbCommand.ExecuteReader()
            While reader.Read()
                If reader.HasRows Then
                    Try
                        Dim input As String
                        input = reader.GetString(0)
                        temp.Add(input)
                    Catch ex As Exception
                        MessageBox.Show(ex.ToString() & " CheckDB")
                    End Try
                End If
            End While
            If (acConn.State = ConnectionState.Open) Then
                acConn.Close()
            End If
        End Using
    End Using
    Return temp
End Function

```

Connection String Redacted for security purposes.