By default, Essbase uses internal mechanisms to decide how to create aggregations. User-defined view selection provides a way for you to influence default view selection and view selection based on query data. See Selecting Views Based on Usage.
Administrators may apply view selection properties to stored hierarchies to restrict Essbase from choosing certain levels for aggregation.
Note: | Secondary hierarchies are either shared or attribute hierarchies. |
Property | Effect |
---|---|
Default | On primary hierarchies, Essbase considers all levels. It does not aggregate on secondary hierarchies unless alternative roll-ups are enabled. |
Consider all levels | Considers all levels of the hierarchy as potential candidates for aggregation. This is the default for primary hierarchies, but not for secondary hierarchies. |
Do not aggregate | Does not aggregate along this hierarchy. All views selected by Essbase are at the input level. |
Consider bottom level only | Applies only to secondary hierarchies. Essbase considers only the bottom level of this hierarchy for aggregation. |
Consider top level only | Applies only to primary hierarchies. Considers only top level of this hierarchy for aggregation. |
Never aggregate to intermediate levels | Applies to primary hierarchies. Selects top and bottom levels only. |
Note: | The bottom level of an attribute dimension consists of the zero-level attribute members. When a secondary hierarchy is formed using shared members, the bottom level comprises the immediate parents of the shared members. |
Essbase considers only views that satisfy the selected view selection properties.
You should be familiar with the dominant query patterns of databases before changing default properties; preventing selection of certain views will make queries to those views slower while improving the speed of other queries. Similarly, enabling Consider All Levels on a secondary hierarchy may speed queries to that hierarchy while making other queries slower.