Which is the correct answer?

You are developing a report which is difficult and cost a lot of time to produce.
You use the technology of SQL Server 2008 Reporting Services (SSRS).
You should make sure that you could set the report server to cache the report for 40 minutes
at the beginning of the request.
Which is the correct answer?

A.
Report snapshots should be run for report.

B.
You should run report execution caching for report.

C.
You should set the data source to utilize a DBCC INDEXDEFRAG.

D.
You should set the data source to utilize a DBCC SHRINKFILE. INDEXDEFRAG

Explanation:
By default, a report is rendered using the most recent data. This means that every execution
starts by reading the database data. This could be a large processing burden on a

production server. To reduce the load on your server, you can cache a temporary copy of a
report. SSRS caches the report in the ReportServer database with all the data but without
any of the rendering information. If a report exists in the cache, when the next user runs the
report, the user gets the data from the cache, and there is no need to reread data from the
database. With report caching, Reporting Services can create and store a copy of the
intermediate format report in a temporary SQL Server database named
ReportServerTempDB in the Execution- Cache table. Even when the first request from a
user follows the schema presented earlier, the processing of subsequent requests is altered
as follows:
1. A request is sent to Report Server.
2. Report Server validates the properties associated with the object requested. If report
execution is set to use the cache, and an item already exists in the ExecutionCache table of
the ReportServerTempDB database for the ReportID of the requested report and the
parameters passed are the same, Report Server renders the report from the stored
intermediate format.
Uusing Report Snapshots for Report Execution
If you cache a report, the fi rst user who runs the report after the cache has expired will have
to wait longer to view the report than the users who follow, because the fi rst user triggers
the data being read from the database. You can prevent this problem by creating a snapshot
of the data in advance of the fi rst report being run. To do this, select the Render This Report
From An Execution Snapshot option in the execution properties of a report. You can create a
snapshot based on a shared or a report-specifi c schedule. In addition, you can create the
first snapshot immediately after you save the execution settings. Another caching
consideration is determining whether previous versions of the cache should be persisted.
Persistence of previous values in reports might be required by business users for
comparison purposes or to be able to refer to those numbers later. Using snapshots, you
can create persistent copies of a report and store those copies in the report history.