29 May 2014

Merging Using XMLA

If partitions have the same aggregation design and structure, you can merge the partition by using the Merge Partitions command in XML for Analysis (XMLA). Merging partitions is an important action to perform when you manage partitions, especially those partitions that contain historical data partitioned by date.

For example, a financial cube may use two partitions:

One partition represents financial data for the current year, using real-time relational OLAP (ROLAP) storage settings for performance.

Another partition contains financial data for previous years, using multidimensional OLAP (MOLAP) storage settings for storage.

Both partitions use different storage settings, but use the same aggregation design. Instead of processing the cube across years of historical data at the end of the year, you can instead use the Merge Partitions command to merge the partition for the current year into the partition for previous years.

This preserves the aggregation data without requiring a potentially time-consuming full processing of the cube.

Specifying Partitions to Merge

When the Merge Partitions command runs, the aggregation data stored in the source partitions specified in the Source property is added to the target partition specified in the Target property.

To be successfully merged, the partitions specified in both the Source and Target must be contained by the same measure group and use the same aggregation design. Otherwise, an error occurs.

The partitions specified in the Source are deleted after the Merge Partitions command is successfully completed.

Note: The Source property can contain more than one partition object reference. However, the Target property cannot.


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