255.Which two statements about the SQL Management Base (SMB) are true? (Choose two.)
A. It contains only SQL profiles generated by SQL Tuning Advisor.
B. It stores plans generated by the optimizer using a stored outline.
C. It is part of the data dictionary and stored in the SYSAUX tablespace.
D. It is part of the data dictionary and stored in the SYSTEM tablespace.
E. It contains the statement log, the plan history, plan baselines, and SQL profiles.
Answer: CE
答案解析：
参考：http://docs.oracle.com/cd/E11882_01/server.112/e41573/optplanmgmt.htm#PFGRF95122
The SQL management base (SMB) is a part of the data dictionary that resides in the SYSAUX tablespace. It
stores statement logs, plan histories, SQL plan baselines, and SQL profiles. To allow weekly purging of unused plans and logs, the SMB uses automatic space management.
You can also add plans manually to the SMB for a set of SQL statements. This feature is especially useful when upgrading the database from a version before Oracle Database 11g because it helps to minimize plan regressions resulting from the use of a new optimizer version.
Because the SMB is located entirely within SYSAUX, the database does not use SQL plan management and SQL tuning features when this tablespace is unavailable.