test for null

[Halon]

Anyone know how to test for a null value being returned from a database query

i tried the code below but think i had too much beer over the long weekend because it should be easy but i can't locate the middle portion of my brain

If myDataSet.Tables(0).Rows(0).Item("Contact") Is Not System.DBNull Then
            contactTemp = ""
        End If

thanks for any help