Which statement describes the information returned by the DBMS_SPACE.SPACE_USAGE procedure for LOB space usage?

Which statement describes the information returned by the DBMS_SPACE.SPACE_USAGE
procedure for LOB space usage?

Which statement describes the information returned by the DBMS_SPACE.SPACE_USAGE
procedure for LOB space usage?

A.
It returns space usage of only BasicFile LOB chunks.

B.
It returns space usage of only SecureFile LOB chunks.

C.
It returns both BasicFile and SecureFile LOB space usage for only nonpartitioned tables.

D.
It returns both BasicFile and SecureFile LOB space usage for both partitioned and
nonpartitioned tables.

Explanation:
SPACE_USAGE Procedures
The first form of the procedure shows the space usage of data blocks under the segment
High Water Mark. You can calculate usage for LOBs, LOB PARTITIONS and LOB
SUBPARTITIONS. This procedure can only be used on tablespaces that are created with
auto segment space management. The bitmap blocks, segment header, and extent map
blocks are not accounted for by this procedure. Note that this overload cannot be used on
SECUREFILE LOBs.

The second form of the procedure returns information about SECUREFILE LOB space
usage. It will return the amount of space in blocks being used by all the SECUREFILE LOBs
in the LOB segment. The procedure displays the space actively used by the LOB column,
freed space that has retention expired, and freed space that has retention unexpired. Note
that this overload can be used only on SECUREFILE LOBs.

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Rodge

Rodge

The answer is wrong, it should be D

The overloaded procedure space_usage from the package dbms_space can be used to monitor the lob segments. There is one procedure for basicfiles and one for securefile lob segments

The exhibit after “show answer” shows the two packages, the first is for basicfiles and the second is for securefiles.
The existence of the “partition_name” column in the procedure demonstrates that partitioned tables are checkable with either procedure.

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Jake from SF

Jake from SF

D is correct:

https://docs.oracle.com/cd/B28359_01/appdev.111/b28393/adlob_smart.htm

DBMS_SPACE.SPACE_USAGE
The existing SPACE_USAGE procedure is overloaded to return information about LOB space usage. It returns the amount of disk space in blocks used by all the LOBs in the LOB segment. This procedure can only be used on tablespaces that are created with auto segment space management.

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