Persistent and Temporary Database Components
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Each database connection in an application is encapsulated by a database component whether you explicitly provide a database component at design time or create it dynamically at runtime. When an application attempts to connect to a database, it either uses an explicitly instantiated, or persistent, database component, or it generates a temporary database component that exists only for the lifetime of the connection.
Temporary database components are created as necessary for any datasets in a data module or form for which you do not create yourself. Temporary database components provide broad support for many typical desktop database applications without requiring you to handle the details of the database connection. For most client/server applications, however, you should create your own database components instead of relying on temporary ones. You gain greater control over your databases, including the ability to
- Create persistent database connections
- Customize database server logins
- Control transactions and specify transaction isolation levels
- Create event notifiers to track when a connection is made or broken