hai i want to connect the sql database to my application . which connectivity is best to connect the sql database. shall i use sqlconnection , sqlcommand , sqldatareader (or) odbcconnection , odbccommand , odbcdatareader.
                                      thank you

Might I suggest going to MSDN and then searching for each of those different classes.

You will then see that some of those serve very different purposes, and should be used in different environments.

Rob
The Developing Developer
Currently Working Towards: MCAD C#
My Blog: http://www.robzyc.spaces.live.com
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In order of preference:

SqlConnection
OleDbConnection
OdbcConnection

If you know you will be connecting to SQL Server then SqlConnection will always be the best option.

/- Sam Judson : Wrox Technical Editor -/

To give you a head start, the ODBC classes can be thought of as a "catch all" for any database that supports an ODBC driver. For example, you can use the ODBC classes to connect to Sql Server, Access, or Oracle. However, since you have indicated that you are using Sql Server I would suggest using the SQL classes since they are optimized for use with Sql Server.

hth.
-Doug

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I think one of the key benefits (feel free to correct me if I am wrong more experienced guys! :)) of using SqlConnection other Connection providers is that it utilises SQL Servers Connection Pooling.

Rob
The Developing Developer
Currently Working Towards: MCAD C#
My Blog: http://robzyc.spaces.live.com

Correct. As I said in my post, the SqlServer classes are specifically optimized to be used with SQL Server (additionally there are connectors that are specific to Oracle and MySQL to name a few) so, as Sam alluded to in his post, if a series of classes are specifically designed for the RDBMS that you are using you should use those.

-Doug

================================================== =========
Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
================================================== =========
.: Wrox Technical Editor / Author :.
Wrox Books 24 x 7
================================================== =========

Hi Doug,

Yeah I know that you should use specialised classes if they exist, just wanted to make sure that I was not talking rubbish when I said connection pooling was one of them!

Thanks for clarifying :)

Rob
The Developing Developer
Currently Working Towards: MCAD C#
My Blog: http://robzyc.spaces.live.com