Getting a ROLAP cube to refresh when a dimension changes

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Have 1 ROLAP cube in an AS DB with other MOLAP cubes. The ROLAP cube is derived from a SQL database view and uses dimensions that are also used by the MOLAP cubes. The aggregation storage of the source view is defined as ROLAP. Updates to the Fact table cause the ROLAP cube to refresh while updates to the dimensions do not cause a refresh of the ROLAP cube.

When for the ROLAP cube ,set storage mode to rolap
and in proactive caching, change settings to Real-time ROLAP
click on "Options" and make sure Enable proactive caching is marked
if now you change a measure in your fact table you will see the change right away
without processing, but the problem is we can not have the same thing working for dimensions
in the same caching setting in Storage Options enabling the check box "Apply settings to dimensions"
doesn't really solve the problem, when you check off this setting
any changes to the dimensions will not update the cube until the dimensions are processed.

What can be done to enable an update of a dimension used by the ROLAP cube to cause the ROLAP cube to be refreshed without reprocessing the MOLAP cubes also using the dimension?

Thanks

If the same dimensions are used in the other MOLAP cubes, you should keep storage mode of your dimensions as MOLAP.

If you wanted to go with storage mode as ROLAP for all of your dimensions, you should create new dimensions that are going to be used only in this ROLAP cube.

You should also take a look whether sizes of your data will allow you to keep the same level of performance- ROLAP will perform slower in general when compared to MOLAP mode.

Edward.
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There should be no need to reprocess the ROLAP cube when you just process the dimension. As long as you are not deleting records from your dimension table, you should just be doing a processAdd or processUpdate on your dimension. This will leave all your cubes in a queryable state and the proactive caching feature should keep your ROLAP partitions "fresh" as new facts arrive.

If you have been doing a processFull on your dimension, it will have been clearing out all the cubes that use the dimension in question as a processFull rebuilds the dimension structure from scratch which requires that dependant cubes have their storage structures rebuilt also.