一些SQL

时间:2021-10-29 07:04:55

复制当前所有,ID自动增长。       insert into test(name,pass) select name,pass from test

删除当前重复      delete A from test A,test B where A.name = B.name and A.pass = B.pass  and A.ID > B.ID

平均薪水大于5000元的部门数据       select deptno,avg(nvl(salary,0)) avg_s from emp_ning where deptno is not null group by deptno having  avg(nvl(salary,0)) >> 5000

计算每个部门的薪水综合和平均薪水      select deptno,sum(salary) sum_s,avg(nvl(salary,0)) avg_s from emp_ning group_by deptno

按部门计算每个部门的最高和最低薪水分别是多少      select deptno,max(salary) max_s,min(salary) min_s from emp_ning group by deptno;

按部门排序,同一个部门按薪水由高到低排序。      select ename,deptno,salary from emp_ning order by deptno,salary desc;

计算员工的平均薪水和薪水总和是多少。      select avg(salary) avg_sal,sum(salary) sum_sal from emp_ning;

计算员工的最高薪水和最低薪水      select max(salary) max_sal,min(salary)min_sal from emp_ning;

模糊查询      select * from emp_ning where job like '%sales%'

in(list),在列表中      select * from emp_ning where job in ('sds','asd');

系统时间      select sysdate from dual;

把时间按照指定格式输出       select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') from dual;

select to_char(sysdate,'year month dd day dy') from dual;

日期相减      select ename,hiredate,(sysdate - hiredate) from  emp;