单项选择题 更新数据表中的记录用以下哪一项( ) A.DELETE B.ALTRE C.UPDATE D.SELECT

单项选择题 以下哪项属于DDL操作( ) A.update B.create C. insert D.delete

单项选择题 以下说法错误的是( ) A.SELECT max(sal),deptno,job FROM EMP group by sal; B.SELECT max(sal),deptno,job FROM EMP group by deptno; C.SELECT max(sal),deptno,job FROM EMP; D.SELECT max(sal),deptno,job FROM EMP group by job;