MDAC 2.5 SDK - OLE DB Programmer's Reference
Chapter 23: Rowsets in OLE DB for OLAP
Updating the value of a cell results in the updating of other dependent properties, such as FORMATTED_VALUE.
Whether or not dependent properties can be updated is provider specific. If they can be updated, it is provider-specific what happens to the determining property (such as VALUE) when a dependent property (such as FORMATTED_VALUE) is updated. For clearer semantics, providers are encouraged to make dependent properties read-only. The OLE DB for OLAP specification does not mandate which properties are dependent on which other properties.
Updating a cell (in other words, the corresponding row in the range rowset) that has an atomic value results in changes to all aggregates based on that cell.
When updating a cell in an aggregated dataset, behavior varies among providers. That is, what happens to the cells that combine to create the aggregate is provider-specific. For example, all cells with the coordinate Qtr1 on this time dimension are aggregate cells because they depend on cells with a month as a coordinate (January, February, and so forth).
Some providers do not allow updates on nonatomic cells. Other providers allow a nonatomic cell to be updated, but they do not change the value of atomic cells beneath the nonatomic cell.
The property MDPROP_AGGREGATECELL_UPDATE can be used by the consumer to determine whether or not a provider supports updating nonatomic cells. If it does, the property also can yield more information about a provider's behavior when such a cell is updated.