Progress
ADM 2 Guide


SmartDataObjects

The SmartDataObject accesses a database directly. It transfers rows, as defined by its database query, to a temp–table called RowObject one batch at a time. (Fields from one or more tables can be joined into a single result table.) For a discussion of the RowObject temp–table, see the "SmartDataObject Query and Update Operations" section in Developing Your Application’s Business Logic."

Once the RowObject temp–table has been built, the SmartDataObject presents its rows to SmartDataViewers, SmartDataBrowsers, and other client objects. The SmartDataObject thus insulates the client objects from the database specifics.

Note that when a SmartDataObject reads a data set into a RowObject temp–table, it provides essentially a snapshot of the current state of the data set, often called a view. The RowObject temp–table does not necessarily reflect updates to the data set that are made by other users in another session; however, any code that executes the openQuery procedure on the data set automatically refreshes the RowObject temp–table with the latest data. Alternatively, you can use the refreshRow function on the current row to get the latest data.

You can customize various field-related properties of a SmartDataObject to meet your own application needs:

SmartDataObjects support update validation logic beyond that defined in the Data Dictionary or in database triggers. For more information, see Developing Your Application’s Business Logic."


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