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anitkumar
04-29-2002, 10:20 PM
Is it feasible to break multidimensional query issued by client to break into independent sub queries and execute those query independently and
diffrent OLAP server which contails similar replica.

jhyde
05-14-2002, 10:14 AM
I can think of several schemes for parallel/distributed execution, none of them particularly straightforward.
One is to leverage parallelism in the underlying RDBMS. The MDX engine may issue several SQL statements for one MDX statement, and the RDBMS could execute some of these in parallel. An RDBMS with partitioning could even execute a single statement (such as a GROUP BY) on multiple nodes.
It's difficult for the client to break one MDX statement into several MDX statements and reassemble them, because of MDX's execution model: first evaluate the axes and the slicer, then compute the cells. All of the MDX fragments would probably have to execute the same axis expressions.
A better scheme is to have a single MDX processor, but to distribute the aggregation manager across multiple machines. The fact table could be partitioned, with different partitions going to different machines. For example, one machine could sum 2002 sales, and another machine could sum all other years.