（141）Exhibit:

View the Exhibit for some of the current parameter settings.

A user logs in to the HR schema and issues the following commands:

SQL>CREATE TABLE emp(empno NUMBER(3), ename VARCHAR2(20), sal NUMBER(8,2));

SQL>INSERT INTO emp(empno,ename)VALUES(1,'JAMES');

At this moment,a second user also logs in to the HR schema and issues the following command:

SQL>ALTER TABLE emp MODIFY sal NUMBER(10,2);

What happens in the above scenario?

A. The second user's session immediately produces the resource busy error.

B. The second user's command executes successfully.

C. The second user's session waits for a time period before producing the resource busy error.

D. A deadlock is created.

答案：（C）

解析：

SQL>update emp set sal=2000 where empno=7788;

1 row updated.

SQL>alter table emp modify deptno number(6);

alter table emp modify deptno number(6)

*

ERROR at line 1:

ORA-00054:resource busy and acquire with NOWAIT specified or timeout expired）

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Oracle 11G OCP 1Z0-053 141