多项选择题
A. It saves disk space and reduces memory usage.
B. It saves disk space but has no effect on memory usage.
C. It incurs extra CPU overhead during DML as well as direct loading operations.
D. It incurs extra CPU overhead during DML but not direct loading operations.
E. It requires uncompress operation during I/O.
单项选择题 WhichstatementistrueregardingtheretentionpolicyfortheincidentsaccumulatedintheAutomaticDiagnosticRepository（ADR）？（）
单项选择题 Examine the following values of the initialization parameters in the database having the SID ORCL: BACKGROUND_DUMP_DEST=/u01/app/oracle/product/11.1.0/db_1/bdump USER_DUMP_DEST=/u01/app/oracle/product/11.1.0/db_1/udump CORE_DUMP_DEST=/u01/app/oracle/product/11.1.0/db_1/cdump DIAGNOSTIC_DEST= The environment variables have the following value: ORACLE_BASE=/u01/app/oracle ORACLE_HOME=/u01/app/oracle/product/11.1.0/db_1 What is the location of the Automatic Diagnostic Repository (ADR) home?（）
单项选择题 Your database is running in ARCHIVELOG mode. You are performing a user-managed backup of the DATA1 tablespace. You place the DATA1 tablespace in backup mode by issuing the following statement: ALTER TABLESPACE data1 BEGIN BACKUP; While you are performing the backup, an error occurs that causes the instance to terminate abnormally. Which statement about the DATA1 tablespace is true?（）