What is Essbase BSO?
Key Concepts for Basic Understanding
Thank you to Jane Story for the presentation on this topic.
The presentation covers the following topics in more detail so be sure to check it out!
- What is the Magic of Essbase?
- What are Dimensions and Members? .
- What is a Block?
- How is Data Stored in BSO?
- Where is Data Stored in BSO?
- Types of Blocks. All Blocks are the same size but what makes them different?
- Where to find BSO Cube Statistics? And how do they relate to what we know?
What is the Magic of Essbase?
- ASO – Aggregate Storage Option : Large outlines, primarily aggregation
- BSO – Block Storage Option: Small outlines, complex analysis/calculation
What are Dimensions and Members?
- A dimension is a view-point on the data.
- Members relating to that dimension/view-point are created within the dimension as a hierarchy.
- Members can be stored, dynamic or navigational aids (label only) or shared to create reporting hierarchies.
- Declared members is the total of ALL members in the dimension (+ Dynamic Time Series for Period).
- Stored members does not include dynamic calc, label only or shared members.
- Each standard dimension in a BSO cube is either DENSE or SPARSE.
What is a Block?
Refer to the presentation for detailed explanation and screenshots.
- The data storage unit in a BSO cube is a BLOCK.
- DENSE & SPARSE determines how big each block is and how many blocks could exist.
- Each standard dimension in a BSO cube can either be DENSE or SPARSE.
- The decision whether a dimension is DENSE or SPARSE is made at design stage.
- DENSE & SPARSE determines how the data is stored in a BSO cube.
- The size and number of BLOCKS, at a high level, will determine how the BSO cube executes operations (retrieves, calculations, reports etc.) and the performance thereof.
- The number of stored members in the DENSE dimensions determines the SIZE of the block.
- The number of stored SPARSE combinations determines the potential number of blocks.
- A new block is created every time data is loaded for that SPARSE combination.
How is Data Stored in BSO?
Refer to the presentation for detailed explanation and screenshots.
- Blocks are created as a combination of Sparse dimensions
- Every Block containing dense dimension references has an Index Point containing sparse dimension references.
- The number of stored members in a dense dimension determines the size of the block.
- The number of stored members in a sparse dimension determines the potential number of blocks, and an index entry is created for each sparse combination.
- The number of each stored member in each dimension is used in these calculations.
- Every block is the same size.
- Dense member data is in EVERY block.
- Sparse member data is only in the blocks for those sparse combinations
Where is Data Stored in BSO?
- Ind/Pag files
- Dense dimensions define data blocks cell location.
- Sparse dimensions define the index, i.e., which block.
Types of Blocks. All Blocks are the same size but what makes them different?
Where to find BSO Cube Statistics? And how do they relate to what we know?
- Activity Report can be used.
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References:
- Presentation – by Jane Story
Reposted with permission from Source.
