Did you read the entire paragraph;
His sample code is using a parameterized method;
"UPDATE [Products] SET [ProductName] = @ProdName, " & _
"[unitPrice] = @UnitPrice, [ProductDescription] = @ProdDesc " & _
"WHERE [ProductID] = @ProductID"
or you can replace the params with variables...(of course you will need to declare and assign these variables yourself)
"UPDATE [Products] SET [ProductName] = '" & myProdName &"', " & _
"[unitPrice] = " & myUnitPrice &", [ProductDescription] = '" & ProdDesc & "' " & _
"WHERE [ProductID] = " & ProdID