Release 10.1A: OpenEdge Development:
Progress Dynamics Advanced Development

Modifying the instance properties

When an SDF uses an SDO as its data source, neither the master nor instance properties of the SDO are available for modification, guaranteeing a fast start up for the dynamic combo. You can, however, programatically alter the SDO instance attributes. The dynamic combo stores the SDO name in the DataSourceName property. With this in hand, you can override the createDataSource( ) function of the dynamic combo. The createDataSource function starts the SDO as an instance in the container (Viewer) and adds the data link from the SDO to the dynamic combo. The defaults of the available SDO instance properties are shown in Table 4–2.

Table 4–2: Instance properties and defaults of an SDO data source

Property	Default
RowsToBatch	0
Shared	True
CacheDuration	If the dynamic combo’s UseCache property is true, then the Unknown value (?) is the default. This denotes an SDO that uses an untimed session cache. Otherwise, the default is zero, denoting that there is no cache. Note: The DynCombo class UseCache property has a default of true.
DataLogicProcedure	Not used. The framework uses a thin dynamic proxy without a DataLogicProcedure on the client for all SDOs, including static ones.