Hello Thamil,
What part of this do you need help with?
A login screen is merely an html page with a form that can be submitted with whatever input is needed to log someone in to your site - usually a unique user name and a password, but can contain other info as requried.
Once you submit that info, you need to "authenticate" the user as being someone who is a "member" - this is often done using a table in the database. If the proper info has been entered, your app would typically set a session variable that is used to indicate the user has been given access to the site or part of the site(authorized). You can also use cookies or hidden variables to pass from request to request that the user is "logged on" but it is most common to use a session variable.
Connecting to an Oracle database is about the same as connecting to any database.
So, specifically, what part of this are you having trouble with?
Woody Z
http://www.learntoprogramnow.com
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