Progress
ADM 2 Guide
SmartDataObject Features and Operating Characteristics
Progress applications require an object that can manage a database query and the associated data update logic. The SmartDataObject serves this purpose. It is designed to meet several key ADM goals:
- UI-independence—SmartObjects that manage the user interface do not manage data and, conversely, SmartDataObjects that manage data do not manage the user interface.
- Open interface—SmartDataObjects can function in an Open4GL environment with non-Progress objects and applications.
- Distributed—SmartDataObjects can function appropriately and efficiently “close to the UI” or “close to the data”; that is, they can function competently at any location within a distributed application.
The SmartDataObject provides the following features:
- A basic database query definition that can be refined at run time
- Query management logic such as open query, repositions, key finds, and sending rows or batches of rows between client and server
- Formatting and other logic in support of one visualization or many separately defined visualizations
- Validation and other data-checking code and business rules
- Database update logic
Note that you can associate business rules or any other required logic with the SmartDataObject.
The operating characteristics of the SmartDataObject make it suitable for heterogeneous environments:
- The SmartDataObject is the only SmartObject that connects directly to the database.
- The SmartDataObject takes a database query and turns it into a temp–table representation that is used by all other SmartObjects.
- The SmartDataObject can be transparently and efficiently distributed using the AppServer.
- The SmartDataObject handles batching rows, performing updates, and reporting errors.
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