多选题

User SCOTT executes the following command on the EMP table but has not issued COMMIT, ROLLBACK, or any data definition language (DDL) command: SQL> SELECT ename FROM emp  2 WHERE job=’CLERK’ FOR UPDATE OF empno;  SCOTT has opened another session to work with the database instance.  Which three operations wouldwait when issued in SCOTT’s second session()

ALOCK TABLE emp IN SHARE MODE;

BLOCK TABLE emp IN EXCLUSIVE MODE;

CUPDATE emp SET sal=sal*1.2 WHERE job=MANAGER;

DINSERT INTO emp(empno,ename) VALUES (1289,’Harry’);

ESELECT ename FROM emp WHERE job=’CLERK’ FOR UPDATE OF empno;

正确答案

来源:www.examk.com

答案解析