Which three are true concerning Storage Indexes?
A.
A maximum of eight table columns for any table are indexed per storage region.
B.
The use of Storage Indexes for particular categories of I/O can be displayed by using an I/O Resource
Manager Category Plan.
C.
Storage Indexes persist across any Exadata storage server reboots.
D.
The use of Storage Indexes for a particular database can be disabled by using an I/O Resource Manager
Database Plan.
E.
A Storage Index is automatically maintained by CELLSRV based on the filter columns of the offloaded SQL.
F.
Different storage regions may have different columns indexed for the same table.
Explanation:
A: Each disk in the Exadata storage cell is divided into equal sized pieces called storage regions (default 1MB).
There is an index entry for every storage regions (1MB of data stored on disk). Each entry contains the minimum and maximum value for columns seen in ‘where’ clause predicates. Information for up to 8 columns can be stored. The index is then used to eliminate disk IO by identifying which storage regions don’t match the
‘where’ clause of a query.