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Part IX: Business Intelligence
The partition view consists of one collapsible pane for each measure group, each pane con-
taining a grid listing the currently defi ned partitions for that measure group.Start the process to add a partition by clicking the New Partition link, which launches a
series of Partition Wizard dialogs:■ (^) Specify Source Information: Choose the appropriate Measure group and data
source view to look in.
■ (^) Restrict Rows: If the source table contains exactly the rows to be included in the
partition, then click Next. If the source table contains more rows than should be
included in the partition, then select the Specify Query to Restrict Rows option,
and the Query box populates. Supply the WHERE clause, and press the Check button
to validate syntax.
■ Processing and Storage Locations: The defaults suffi ce for most situations. If nec-
essary, choose options to balance the load across disks and servers.
■ Completing the Wizard: Supply a name for the partition — generally the same
name as the measure group suffi xed with the partition slice (for example,
Internet_Orders_2004). If aggregations have not been defi ned, defi ne them
now or copy them from another partition.
When a partition has been added, you can edit the name and source by clicking in the
appropriate cell in the partition grid.
Aggregation Design
The best trade-off between processing time, partition storage, and query performance is
defi ning only aggregations that help answer queries commonly run against a cube. Analysis
Services’ usage-based optimization tracks queries run against the cube and then designs
aggregations to meet that query load, but it requires a period of production use to gather
sample data.
A good approach is to fi rst create a modest number of aggregations using the Aggregation
Design Wizard and assign that design to all active partitions. Then deploy the cube for use
to collect a realistic query history, and run the Usage Based Optimization Wizard.
Aggregation Design Wizard
Aggregation Design Wizard creates aggregations based on intelligent guesses. Invoke the
wizard from the toolbar on the Aggregations tab of the cube designer. The wizard steps
through several pages:
■ (^) Select Partitions to Modify: The wizard runs based on the currently selected mea-
sure group. Check all the partitions that you want to update.
■ (^) Review Aggregation Usage: Here defaults generally suffi ce, but options include
Full — include in every aggregation; None — don’t include in any aggregation;
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