On Mon, 2 Aug 2004 21:23:05 +0100 (BST), Research labs <[EMAIL PROTECTED]> wrote: > Jim, > > Thanks for your response. > I want each user to login to the database(MySQL), via > a JSP. Once logged in, I want them to use their > database username (specified at log in time) for > communicating with the database throught their > session. To put it another way, if 4 users are > currently logged in (via a JSP etc.), When I query the > data dictionary of the database, I want their names to > come up. At any point in time, I want to be able to > find out, who is logged in, this is why I do not want > everyone to log in with the same username and password > e.g. ola/ola-hardcoded in the Struts config's > data-source. >
Do you care about finding out who is logged in to your *application*, or who is logged in to the *database*? Those can easily be made separate questions, and in most cases should be separate. > I do not mind using any datasource so long as I can > achieve my objective. > The <data-source> element in struts-config.xml, like using most JNDI provided data sources, will not address your need. That is because they create application wide pools for shared connections. Doing what you want to do, however, will also be giving up on the key advantage of using a data source in the first place -- sharing a small number of database connections between multiple users. By definition, if you are using per-user logins to the database, such connections cannot be shared. That can be problematic for the scalability of your app, because it will require more database resources to be allocated than would otherwse be necessary. Plus, you'll likely run into limits on how many individual database connections can be opened before you'd ever run out of capacity in your web server to support simultaneous users. If all you care is logins to an application, here's a couple of easy ways to do that while still sharing database connections: * At login time, write into some table someplace a row for the logged in user, and make sure you clean it up when they log out or when the session expires. To see who is logged in, run database queries against this table. * Store some in-memory data structure (perhaps as an application scope attribute), and have the login/logout logic add and remove entries from this data structure. To see who is logged in, set up a Struts action or something that will go through the data structure and list all the logged on users. If you still really want per-user database logins, then give up on the idea of using any sort of data source -- it won't buy you anything. Instead, create a standalone JDBC connection at login time, and store it in session scope somewhere. But I would suggest you consider the disadvantages of such an approach before using it. > Thanks. > Ola. > Craig --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
