以下语句正确的是() A: select<br/>sal+1 from emp; B: select<br/>sal*10,sal*deptno from emp; C: 不能使用运算符号 D: select<br/>sal*10,deptno*10 from emp;

以下能删除表的语句是( ) A: Delete * from emp B: Drop database emp C: Drop * from emp D: delete database emp

以下语句不正确的是( ) A: select * from emp; B: select ename,hiredate,sal from emp; C: select * from emp order deptno; D: select * from where deptno=1

查询员工表emp中的第3条到第8条记录。显示emp表中的全部字段。( ) A: select rownum rn,emp.* from emp where rownum3; B: select * from(select rownum RN,emp.* from emp where RN3; C: select * from(select rownum RN,emp.* from emp where rownum3; D: select rownum RN,emp.* from emp where RN3;

下面删除记录的语句正确的是( ) A: delete from emp where name="Tony"; B: delete * from emp where name="Tony"; C: drop from emp where name="Tony"; D: drop * from emp where name="Tony";

 以下语句不正确的是(     ) A: select * from emp B: select ename,hiredate,sal from emp C: select * from emp order deptno D: select * from where deptno=1 and sal<300

统计每个部门中人数的语句是？ A: select count(id) from emp order by deptno; B: select sum(id) from emp order by deptno; C: select count(id) from emp group by deptno; D: select sum(id) from emp group by deptno;

设有职工基本表：EMP(ENO，ENAME，AGE，SEX，SALARY)，其属性分别表示职工号、姓名、年龄、性别、工资。为每个工资低于平均工资的女职工加薪200元，以下SQL语句正确的是______。 A: UPDATE EMP SET SALARY=SALARY+200 B: WHERE SALAEY＜(SELECT AVG(SALARY)FROM EMP) AND SEX=’女’ C: UPDATE FROM EMP SET SALARY=200 D: WHERE SALAEY＜(SELECT SUM(SALARY)FROM EMP)AND SEX=’女’ E: UPDATE EMP SET SALARY=200 F: WHERE SALAEY＜(SELECT AVG(SALARY)FROM EMP)AND SEX=’女’ G: UPDATE FROM EMP SET SALARY=SALARY+200 H: WHERE SALAEY＜(SELECT SUM(SALARY)FROM EMP)AND SEX=’女’

以下哪个查询操作能够实现将员工的参加工作日期按如下格式显示：月份/年份。 A: select ename,hiredate,to_char(hiredate,'HH/RR') from emp; B: select ename,hiredate,to_char(hiredate,'MM/RR') from emp; C: select ename,hiredate,to_char(hiredate,'MON') from emp; D: select ename,hiredate,to_char(hiredate,'DD/YY') from emp;

在MYSQL数据库中以下语句错误的是（） A: select-sal+1from-emp； B: select-sal*10，sal*deptnofrom-emp； C: select-sal*10，deptno*10-from-emp； D: select-sal*10，deptno*10-TO-emp；