Babu, I would like to answer your questions one by one. Qn 1: If you are using both SQL Server and Oracle, you can use both the namepaces. System.Data.SqlClient as well as System.Data.OracleClient. but my professional solution is, you better to use OleDB namespace, so tat, you can write custom function to generate/establish the connection for your different DB servers. Qn 2: Viewstate comes in Two different phases, 1. Load View State (next to initilialize phase), 2. Save View State(next to prerender phase) Load View State At the end of this phase, the ViewState property of a control is automatically populated as described in Maintaining State in a Control. A control can override the default implementation of the LoadViewState method to customize state restoration. Save View State
The ViewState property of a control is automatically persisted to a string object after this stage. This string object is sent to the client and back as a hidden variable. For improving efficiency, a control can override the SaveViewState method to modify the ViewState property. Qn 3: You can convert Reference type into value type(Unboxing) in terms of explicit manner. Qn 4: You can convert you variable into DateTime using System.DateTime before pass the parameter value into SP. Thanx, Smith | 
