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cache updates and by the time of the 4 hour time limit you do have a new
MOLAP cache ready for users to query. There might be some times where
you have frequent data updates on relational database and your MOLAP re-
building has not completed but latency has expired. During that time all re-
quests will be served by retrieving results from the data source. You need to
ensure this time period is as small as possible so that users perceive the data
is real-time and with very good performance (due to MOLAP cache).
Figure 18-15
Analysis Services serves data to users with the help of a cache. If the data in
the relational data warehouse changed, the cache needs to be updated (that
is, rebuilt). It takes some amount of time to rebuild the cache. Latency is one
of the proactive caching properties that allows you to control serving your
customers from an old MOLAP cache for a certain period of time; or to in-
stantaneously serve the customers with the latest data. If your users are con-
cerned about getting the most up-to-date data, you would set the property
called Latency to zero. This informs the Analysis Services that users are in-
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