By default, Essbase uses internal mechanisms to decide how to create aggregations. User-defined view selection provides a way for an administrator to influence both default and query-based view selection.
When you select a stored member in an aggregate storage outline, icons appear in the Outline Editor toolbar enabling you to modify selection properties for that member. You can also set these properties in the Member Properties Dialog Box—Information Tab dialog box, under Level Usage for Aggregation. You can select from the following options:
| Property | Effect |
|---|---|
 Default | On primary hierarchies, Essbase considers all levels. It does not aggregate on secondary hierarchies unless alternative rollups 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 top level only | Applies only to primary hierarchies. Queries are answered directly from input data. |
 Never aggregate to intermediate levels | Applies to primary hierarchies. Selects top and bottom levels only. |
Understanding User-Defined View Selection in the Oracle Essbase Database Administrator's Guide