To be an EPM Architect, you must speak the language of the 'Tree'. Essbase uses two different numbering systems to track where a member sits in your outline.
1. The Definitions: Heritage vs. Status
* Generations (Top-Down): Numbered from the root down. Generation 1 is always the Dimension name. Numbers increase as you go deeper.
* Levels (Bottom-Up): Numbered from the leaves up. Level 0 is the most important—it represents the 'Leaf' members where data lives.
2. The "Family Tree" Example
Think of your own family history:
* Generation View:
* Gen 1: Your Great-Grandfather.
* Gen 2: Your Grandfather.
* Gen 3: Your Father.
* Level View:
* Level 0: You (The leaf—you have no children yet).
* Level 1: Your Father (One step above the leaf).
Why use Levels? In a complex organization, 'New York' might be 4 steps deep, while 'London' is only 2 steps deep. Level 0 finds them both because they are both 'Leaves,' even if their Generation numbers are different.
3. How it is useful while building an application
* Data Integrity: We almost always load data to Level 0. If you load to a parent, your consolidations will likely break.
* Automation: When writing a report, you don't list every account. You simply ask for 'Level 0 of Total Assets.' If you add an account next year, the report updates itself!
* Speed: Level 0 data is 'stored' data. It is the fastest data to retrieve.
4. Where do we use these concepts?
* Calc Scripts: Using commands like '@RELATIVE("Entity", 0)' to target only the bottom-level departments.
* Smart View: Using the 'Zoom to Level 0' feature to quickly see the lowest level of detail.
* Reporting: Filtering a 'Headcount' report to show only Gen 3 (Regional Managers).
5. Extra Information: Generation Names
A pro-architect tip: You can assign 'Names' to these levels. Instead of telling a user to 'Filter by Gen 2,' you can name it 'Region' in the outline. This makes the system much more user-friendly for the Finance team.