Select the correct statement.
A.
Cache provides fast and always up-to-date information.
B.
Cache can increase traffic to back end database.
C.
Cache needs to be purged to refresh data.
D.
Cache can degrade query performance by reading data from the disk instead of the database.
E.
Cache is seeded by manually running PL/SQL at the back end database.
Explanation:
In a standard OBIEE implementation, we generally want to purge and re-build the
cache after every ETL (extract, transform, and load) run.
C
e) is incorrect, the cache seed definition is as below:
http://www.rittmanmead.com/2015/09/obiee-bi-server-cache-management-strategies/
Seeding the Cache
Bob runs an OBIEE dashboard, and the results are added to the cache so that when Bill runs the same dashboard Bill gets a great response rate because his dashboard runs straight from cache. Kinda sucks for Bob though, because his query ran slow as it wasn’t in the cache yet. What’d be nice would be that for the first user on a dashboard the results were already in cache. This is known as seeding the cache, or ‘priming’ it.
There are several options for seeding the cache.
1.Run the analysis manually, which will return the analysis data to you and insert it into the BI Server Cache too.
2.Create an Agent to run the analysis with destination set to Oracle BI Server Cache (For seeding cache), and then either:
1.Schedule the analysis to run from an Agent on a schedule
2.Trigger it from a Web Service in order to couple it to your ETL data load / cache purge batch steps.
3.Use the BI Server Procedure SASeedQuery to load the given query into cache without returning the data to the client. This is useful for doing over JDBC/ODBC/Web Service. You could just run the Logical SQL itself, but you probably don’t want to pull the actual data back to the client, hence using the procedure call instead.
a) is incorrect, cache data could be stale data
b) is incorrect, cache can decrease the traffic
d) is incorrect, cache can upgrade the performance even though the cache is stored in the disk file