The default behavior of the interface DLL is for applications to wait for completion of each database request before carrying out other functions. This behavior can be changed using request management functions. For example, when using Interactive SQL, the operating system is still active while Interactive SQL is waiting for a response from the database and Interactive SQL carries out some tasks in that time.

You can achieve application activity while a database request is in progress by providing a callback function. In this callback function, you must not do another database request except db_cancel_request. You can use the db_is_working function in your message handlers to determine if you have a database request in progress.

The db_register_a_callback function is used to register your application callback functions.

• db_register_a_callback function
• db_cancel_request function
• db_is_working function

The db_backup function provides support for online backup in embedded SQL applications. The backup utility makes use of this function. You should only need to write a program to use this function if your backup requirements are not satisfied by the SQL Anywhere backup utility.

You can also access the backup utility directly using the Database Tools DBBackup function. See DBBackup function.

• db_backup function