User SCOTT executes the following command on the EMP table but has not issued COMMIT, ROLLBACK, orany data definition language (DDL) command: SQL> SELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno; SCOTT has opened another session to work with the database instance. Which three operations would waitwhen issued in SCOTT’s second session()
- A、LOCK TABLE emp IN SHARE MODE;
- B、LOCK TABLE emp IN EXCLUSIVE MODE;
- C、UPDATE emp SET sal=sal*1.2 WHERE job=ANAGER?UPDATE emp SET sal=sal*1.2 WHERE job=?ANAGER?
- D、INSERT INTO emp(empno,ename) VALUES (1289,’Harry’);
- E、SELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno
正确答案:A,B,E
答案解析:有

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