创建派生类时，可以通过NotInheritable创建不能作为基类的类。
Evaluate the set of SQL statements: CREATE TABLE dept (deptno NUMBER(2), dname VARCHAR2(14), loc VARCHAR2(13)); ROLLBACK; DESCRIBE DEPT What is true about the set?（） The DESCRIBE DEPT statement displays the structure of the DEPT table.。 The ROLLBACK statement frees the storage space occupied by the DEPT table.。 The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.。 The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.。
影响绝缘油的绝缘强度的主要因素是（）。 油中含杂质水分。 油中含酸值偏高。 油中氢气偏高。
A new report process containing a complex query is written, with high impact on the database. You wantto collect basic statistics about query, such as the level of parallelism, total database time, and the number of I/O requests. For the database instance STATISTICS_LEVEL, the initialization parameter is set to TYPICAL and theCONTROL_MANAGEMENT_PACK_ACCESS parameter is set to DIAGNOSTIC+TUNING. What should you do to accomplish this task?（） Execute the query and view Active Session History (ASH) for information about the query.。 Enable SQL trace for the query.。 Create a database operation, execute the query, and use the DBMS_SQL_MONITOR. REPORT_SQL_MONITOR function to view the report.。 Use the DBMS_APPLICATION_INFO.SET_SESSION_LONGOPS procedure to monitor query execution and view the information from the V$SESSION_LONGOPS view.。
根据《反家庭暴力法》的规定，人身安全保护令的有效期不超过（）。 一年。 五个月。 三个月。 六个月。
You work as a database administrator for Certkiller .com. In the middle of a transaction， a user session was abnormally terminated but the instance is still up and the database is open. Which two statements are true in this scenario？（）
