万事俱备之ORACLE_SQL 练手目录和 part1

重点内容：
1.提供下载ORACLE SQL：经典查询练手系列文章收尾(目录篇)
2.纯净版 ORACLE_SQL练手
更多内容：
ORACLE_SQL 练手 part2
ORACLE_SQL 练手 part3
ORACLE_SQL 练手 part4
ORACLE_SQL 练手 part5
脚本下载：
ORACLE_SQL练手 脚本

-----------Some methods for searching table------------
--查找指定用户下的表
SELECT * FROM ALL_TABLES WHERE OWNER='UAT_ADAM_ODS' ;
--查找owner
select owner from all_tables where table_name like '%TMFDBPCALMBR%';
select owner from all_tables where table_name = 'RPAS_TMFDBPCALMBR';
SELECT table_name FROM ALL_TABLES WHERE   table_name like '%TMFDBPCALMBR%';
select owner from all_tables where table_name = 'ADAM_MEMBER_INFO_TEMP';

--emp
create table EMP 
(
  empno    INTEGER,
  ename    VARCHAR2(50),
  job      VARCHAR2(50),
  mgr      INTEGER,
  hiredate DATE,
  sal      NUMBER(10,2),
  comm     NUMBER(10,2),
  deptno   INTEGER
);

insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (104, 'huyong', 'PM', 1455, to_date('26-05-2011', 'dd-mm-yyyy'), 5500, 14, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (105, 'WANGJING', 'Developer', 1455, to_date('26-05-2011', 'dd-mm-yyyy'), 5500, 14, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (102, 'EricHu', 'Developer', 1455, to_date('26-05-2011', 'dd-mm-yyyy'), 5500, 14, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (1455, 'Robot', 'QM', null, to_date('06-04-2011', 'dd-mm-yyyy'), 8500, 14, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7369, 'SMITH', 'CLERK', 7902, to_date('17-12-1980', 'dd-mm-yyyy'), 800, 0, 20);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7499, 'ALLEN', 'SALESMAN', 7698, to_date('20-02-1981', 'dd-mm-yyyy'), 1600, 300, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7521, 'WARD', 'SALESMAN', 7698, to_date('22-02-1981', 'dd-mm-yyyy'), 1250, 500, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7566, 'JONES', 'MANAGER', 7839, to_date('02-04-1981', 'dd-mm-yyyy'), 2975, 0, 20);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7654, 'MARTIN', 'SALESMAN', 7698, to_date('28-09-1981', 'dd-mm-yyyy'), 1250, 1400, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7698, 'BLAKE', 'MANAGER', 7839, to_date('01-05-1981', 'dd-mm-yyyy'), 2850, 0, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7782, 'CLARK', 'MANAGER', 7839, to_date('09-06-1981', 'dd-mm-yyyy'), 2450, 0, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7788, 'SCOTT', 'ANALYST', 7566, to_date('19-04-1987', 'dd-mm-yyyy'), 3000, 0, 20);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7839, 'KING', 'PRESIDENT', null, to_date('17-11-1981', 'dd-mm-yyyy'), 5000, 0, 10);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7844, 'TURNER', 'SALESMAN', 7698, to_date('08-09-1981', 'dd-mm-yyyy'), 1500, 0, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7876, 'ADAMS', 'CLERK', 7788, to_date('23-05-1987', 'dd-mm-yyyy'), 1100, 0, 20);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7900, 'JAMES', 'CLERK', 7698, to_date('03-12-1981', 'dd-mm-yyyy'), 950, 0, 30);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7902, 'FORD', 'ANALYST', 7566, to_date('03-12-1981', 'dd-mm-yyyy'), 3000, 0, 20);
insert into EMP (empno, ename, job, mgr, hiredate, sal, comm, deptno)
values (7934, 'MILLER', 'CLERK', 7782, to_date('23-01-1982', 'dd-mm-yyyy'), 1300, 0, 10);
commit;

--dept
create table DEPT
(
  deptno INTEGER,
  dname  VARCHAR2(50),
  loc    VARCHAR2(50)
);

insert into DEPT (deptno, dname, loc)
values (20, 'RESEARCH', 'DALLAS');
insert into DEPT (deptno, dname, loc)
values (30, 'SALES', 'CHICAGO');
insert into DEPT (deptno, dname, loc)
values (40, 'OPERATIONS', 'BOSTON');
insert into DEPT (deptno, dname, loc)
values (50, '50abc', '50def');
insert into DEPT (deptno, dname, loc)
values (60, 'Developer', 'HaiKou');
insert into DEPT (deptno, dname, loc)
values (10, 'ACCOUNTING', 'NEW YORK');
commit;

--练习和答案
INSERT INTO EMP VALUES (102, 'EricHu', 'Developer',1455, DATE '2011-5-26', 5500.00,14.00,10 );
--count group by
select *  from (select empno,count(empno) as num from emp   group by empno) t1  where num>1;

delete  from emp 
        where  empno in (select empno as num from emp   group by empno having count(*)>1) 
        and rowid not in (select min(rowid) from emp group by empno having count(*)>1);

select * from emp;     
select * from dept;
--------1．列出至少有一个员工的所有部门。---------  
select distinct(dname) from emp left join dept on emp.deptno = dept.deptno ;
select dname from dept where deptno in (select deptno from emp where count(deptno)>1);
select dname from dept where deptno in (select deptno from emp  group by deptno having count(deptno)>1);

--------2．列出薪金比“SMITH”多的所有员工。----------  
select ename,sal from emp where sal>(select sal from emp where ename='SMITH');

--------3．列出所有员工的姓名及其直接上级的姓名。----------  
select a.ename,b.ename as mag_name from emp a,emp b where b.empno=a.mgr;
select a.ename,(select ename from emp b where b.empno=a.mgr) as boss_name from emp a;   

--------4．列出受雇日期早于其直接上级的所有员工。----------  
select a.ename from emp a,emp b where b.empno=a.mgr and a.hiredate<b.hiredate;
--细
select a.ename from emp a where a.hiredate<(select hiredate from emp b where b.empno=a.mgr);   
--------5．列出部门名称和这些部门的员工信息，同时列出那些没有员工的部门----------  
--join on
select a.deptno,a.dname,b.empno,b.ename from dept a  left join emp b on a.deptno=b.deptno;
--------6．列出所有“CLERK”（办事员）的姓名及其部门名称。----------  
select a.ename,b.dname from emp a join dept b on a.deptno=b.deptno and a.job='CLERK';  
--------7．列出最低薪金大于1500的各种工作。----------  
--min(x) > y
select *  from (select job,min(sal) ms from emp  group by job ) where ms>1500;
select distinct job as HighSalJob，min(sal) from emp group by job having mi+n(sal)>1500;   
--------8．列出在部门“SALES”（销售部）工作的员工的姓名，假定不知道销售部的部门编号。----------  
--不知到就不连接，直接筛选出来，做in判断
select ename from emp where deptno=(select deptno from dept where dname='SALES');  
--------10．列出与“SCOTT”从事相同工作的所有员工。--------  
select empno,ename from emp where job = (select job from emp where ename='SCOTT');
--------11．列出薪部门中多于1人的所有部门员工信息。---------  
-- where & gb having .count/min/max X  to select X / group by X 
select ename,empno,job,deptno,sal from emp where job in( select job from emp   group by job having count(*)>1);
--------12．列出薪金高于在部门30工作的所有员工的薪金的员工姓名和薪金。---------  
--not in max/min/count need to be in group by
select ename,sal from emp where sal> (select max(sal) from emp  group by deptno having deptno=30);
--------12．列出平均薪水的员工及薪水。---------  
select deptno,count(*),avg(sal) from emp group by deptno;

select emp.deptno,dname,min(sal) from emp left join dept on emp.deptno=dept.deptno group by emp.deptno,dname;
select job,min(sal) from emp  group by job;
--
update  emp SET comm=0 where comm is null;
select comm from emp;
---------14．列出所有员工的姓名、部门名称和工资。---------  
-- nvl()null处理
select ename,(sal+comm)*12 salinyear from emp order by salinyear desc;
select ename,(sal+nvl(comm,0))*12 as salpersal from emp order by salpersal desc;  
---------19．用一条sql语句查询出scott.emp表中每个部门工资前三位的数据，显示结果如下：
 select 
       deptno,
       max(sal)sal1,
       max (decode(rn, 2, sal) )sal2,
       min(sal)sal3
from ( select sal,deptno,row_number() over(partition by deptno order by sal desc) rn from emp )
where rn<4
group by deptno
;
--
select deptno,max(sal) sal1,max(decode(rn,2,sal)) sal2,min(sal) sal3
from
(select sal,deptno,rn from(select deptno,sal,row_number() 
over (partition by deptno order by sal desc) rn from emp) e
where e.rn<=3)
group by deptno；