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HomeDatabaseMysql TutorialOracle的sql语句练习题含答案

--1、选择部门30中的雇员 select * from emp where deptno=30; --2、列出所有办事员的姓名、编号和部门 select ena

  --1、选择部门30中的雇员

  select * from emp where deptno=30;

  --2、列出所有办事员的姓名、编号和部门

  select ename,empno,dname from emp e inner join dept d on e.deptno = d.deptno where job=upper('clerk’);

  --3、找出佣金高于薪金的雇员

  select * from emp where comm>sal;

  --4、找出佣金高于薪金60%的雇员

  select * from emp where comm>sal*0.6

  --5、找出部门10中所有经理和部门20中的所有办事员的详细资料

  select * from emp where (deptno=10 and job=upper('manager')) or (deptno=20 and job=upper('clerk '));

  --6、找出部门10中所有经理、部门20中所有办事员,既不是经理又不是办事员但其薪金>=2000的所有雇员的详细资料

  select * from emp where (deptno=10 and job=upper('manager')) or (deptno=20 and job=upper('clerk ')) or (jobupper(‘manager’) and jobupper(‘clerk’) and sal>=2000)

  --7、找出收取佣金的雇员的不同工作

  select distinct job from emp where comm>0;

  --8、找出不收取佣金或收取的佣金低于100的雇员

  select * from emp where nvl(comm,0)

  --9、找出各月最后一天受雇的所有雇员

  select * from emp where hiredate= last_day(hiredate);

  --10、找出早于25年之前受雇的雇员

  select * from emp where months_between(sysdate,hiredate)/12>25;

  select * from emp where hiredate

  --11、显示只有首字母大写的所有雇员的姓名

  select ename from emp where ename=initcap(ename);

  --12、显示正好为6个字符的雇员姓名

  select ename from emp where length(ename)=6

  --13、显示不带有'R'的雇员姓名

  Select ename from emp where ename not like ‘%R%’;

  Select ename from emp where instr(ename,’R’)=0;

  --14、显示所有雇员的姓名的前三个字符

  select substr(ename,1,3) from emp

  --15、显示所有雇员的姓名,用a替换所有'A'

  Select replace(ename,’A’,’a’) from emp

  --16、显示所有雇员的姓名以及满10年服务年限的日期

  Select ename,add_months(hiredate,12*10) ‘服务年限的日期’ from emp

  --17、显示雇员的详细资料,按姓名排序

  Select * from emp order by ename

  --18、显示雇员姓名,根据其服务年限,将最老的雇员排在最前面

  Select ename from emp order by hiredate

  --19、显示所有雇员的姓名、工作和薪金,按工作的降序顺序排序,而工作相同时按薪金升序

  Select ename,job,sal from emp order by job desc ,sal asc

  --20、显示所有雇员的姓名和加入公司的年份和月份,按雇员受雇日所在月排序,将最早年份的项目排在最前面

  select ename,to_char(hiredate,'yyyy'),to_char(hiredate,'mm') from emp order by hiredate asc

  --21、显示在一个月为30天的情况下所有雇员的日薪金

  select ename,sal/30 from emp;

  --22、找出在(任何年份的)2月受聘的所有雇员

  select * from emp where to_char(hiredate,'mm')='02';

  --23、对于每个雇员,,显示其加入公司的天数

  select ename,sysdate-hiredate from emp

  --24、显示姓名字段的任何位置,包含 "A" 的所有雇员的姓名

  select ename from emp where ename like '%A%';

  select ename from emp where instr(ename,’A’,1)>0;

  --25、以年、月和日显示所有雇员的服务年限

  Select months_between(sysdate,hiredate)/12 as “年”, months_between(sysdate,hiredate) as “月”, sysdate-hiredate as “日” from emp

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