Professional Microsoft® SQL Server® Analysis Services 2008 with MDX

Chapter 12. Data Writeback

In previous chapters you saw how metadata constituting OLAP databases (the UDM) can be manipulated using the Analysis Services 2008 development environment. You learned that the metadata changes are propagated to the Analysis Services instance through Create or Alter statements. You've also learned that Analysis Services reads data from relational sources during processing. You learn more about how processing is used to update cubes and dimensions with the latest data in the relational source in Chapter 13.

However, what if you want to update data in your cube or in a dimension it contains without going directly to the relational source? For example, change of marital status for an employee, where marital status is an attribute within the Employee dimension, or perhaps an update for the next fiscal year's budget based on the current year's revenue where budget is a measure within your cube. Analysis Services 2008 provides you with the ability to directly update dimension as well as cube data. Data updates within your UDM are referred to as a writeback because you are writing data back into an existing UDM. Updating members within your dimension is referred to as dimension writeback and updating the measure values within your cube is called cell writeback. By the way, don't let the three letter acronym throw you off; a UDM is another way of referring to a cube.

Dimension writeback enables a user to add, update, or delete dimension members while working ...