Cache Mode
The cache mode defines whether and how the query results and navigational states calculated by the OLAP processor should be saved as highly compressed data in a cache.
The mode can be set as the default value for an InfoProvider in Customizing and for a query in the query monitor.
Caching is a means of improving query performance. Care should be taken to balance benefits against cost however:
- Benefits: Better query response time
- Cost: Expenditure involved in structuring and storing data in the cache
You can store cache data in the database or locally at runtime. The option that you choose depends on various parameters. These include:
How often the query is requested
We recommend saving frequently requested queries in the cache. There are practically no limitations on the memory space available in the database for the database cache.
The complexity of the query
Caching improves performance for queries whose evaluation is more complex. We recommend keeping complex data processed by the OLAP processor in the cache.
How often data is loaded
The cache does not constitute an advantage if query-relevant data is frequently changed and therefore has to be loaded frequently, since the cache has to be regenerated every time.
Cache mode I: Cache is inactive
New data is read during every single navigation step.
Cache mode 0: Local cache
The database cache is deactivated. In this case, the system works exclusively with the local cache.
Cache mode D: Cache in database
The cache data is persistent in database tables. In this mode, no data is displaced, and the memory size is unlimited. The database instance for the table carries the load. More space is required, but this method also saves time.
Cache mode P: Every provider as set in the InfoProvider definition
This mode is only available for queries on MultiProviders and CompositeProviders. It makes it possible to cache the data from the contained InfoProviders in accordance with the cache made set in the definition of each individual InfoProvider.