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Adding a Session to the Web Module
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Console CGI applications are launched in response to HTTP request messages. When working with databases in these types of applications, you can use the default session to manage your database connections, because each request message has its own instance of the application. Each instance of the application has its own distinct, default session.

When writing an ISAPI application or an NSAPI application, however, each request message is handled in a separate thread of a single application instance. To prevent the database connections from different threads from interfering with each other, you must give each thread its own session.

Each request message in an ISAPI or NSAPI application spawns a new thread. The Web module for that thread is generated dynamically at runtime. Add a TSession object to the Web module to handle the database connections for the thread that contains the Web module.

Separate instances of the Web module are generated for each thread at runtime. Each of those modules contains the session object. Each of those sessions must have a separate name, so that the threads that handle separate request messages do not interfere with each other's database connections. To cause the session objects in each module to dynamically generate unique names for themselves, set the AutoSessionName property of the session object. Each session object will dynamically generate a unique name for itself and set the SessionName property of all datasets in the module to refer to that unique name. This allows all interaction with the database for each request thread to proceed without interfering with any of the other request messages. For more information on sessions, see Managing database sessions.

See Also

Types of Web Server Applications

Writing Multi-threaded Applications

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