For each dimension, select the levels that you want to precalculate. The base level should always be selected. The methodology is different depending on whether the cube uses compressed or regular composites.
Dimension
Select each dimension to display its levels.
Levels
Select the levels you wish to calculate and store as part of the build process.
Regular Composites: Use skip-level aggregation on one or two dimensions, but not more than half the dimensions in the cube. Fully aggregate the other dimensions. For skip-level aggregation, the best method for identifying levels for stored data is to determine the ratio of dimension members at each level, and to keep the ratio of members to be calculated on the fly at less than 10:1. This method assures that all answer sets can be returned quickly. You can modify this ratio using your judgment on how frequently a level is accessed.
Compressed Composites: Do not aggregate the dimension with the most members. If there are several dimensions that are the about same size, choose the one with the most levels. Fully aggregate the other dimensions except for the top level. You can modify these general rules depending on the structure of your data. For example, you may aggregate a top level where the number of children is extremely high, or you may skip a level that you know is seldom queried.
Slower varying dimensions take longer to aggregate because the data is scattered throughout its storage space. If you are optimizing for data maintenance, then fully aggregate the faster varying dimensions and use skip-level aggregation on the slower varying dimensions.
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