[每日一題] OCP1z0-047 :2013-07-15 drop column

如下實驗： 　[email protected]> Create table emp( 2Empno number(4) not null, 3First_name varchar2(20), 4Last_name varchar2(20), 5Salary number(10,2), 6Deptno number(2) 7 ); Table created. [email protected]>

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