Oracle sql 常用操作

1.创建一个表：  (Oracle database)
create table stu
(
    id int,
    name varchar(20),
    sex varchar(10),
    age int
);

2.向已有的表中插入一行数据：
insert into stu(id,name,sex,age) values(1,‘huhu‘,‘man‘,20);
insert into stu(id,name,sex,age) values(212,‘huiny‘,‘woman‘,22);
insert into stu(id,name,sex,age) values(315,‘灰灰‘,‘男‘,23);

3. 查寻表中元素
    1.查询所有 select *from stu;
    2.查询部分(某几列) select id,sex from stu;
    3.查询部分(某几行) select *from stu where id=1;
    4.查询表中记录条数 select count(*) from stu;
4.删除 
    1.删除表中记录 delete from stu where id=1;
    2.删除表 drop table stu;
    
5.修改
    update from ...;

6.约束
    1.在表中直接添加约束
        primary key(主键)
        unique(唯一)
        check(检查) 例：check(stusex in(‘男‘,‘女‘))
        not null(非空)
        foreign key(外键) 1.数据复用 2.字段可以拆成两列 
            1.两个表有关系，用外键
            2.(一般)在元素多的一方加外键，(偶尔)考虑方向问题，不要造成数据重复

            
            
1.创建司机表
create table driver_table
(
    flowid number(12) primary key,
    driver_name varchar2(90),
    driver_sex varchar2(20)
);
;创建车辆表
create table vehicle_table
(
    vehicle_id number(12) primary key,
    vehicle_type varchar2(90),
    vehcile_num varchar2(90),
    driver_id number(12) references driver_table(flowid)
);

3.删除两个表
drop table driver_table;
drop table vehicle_table;

4.向两个表中插入数据
insert into driver_table(flowid,driver_name,driver_sex) values(1,‘yangee‘,‘nan‘);
insert into vehicle_table(vehicle_id,vehicle_type,vehcile_num,driver_id) values(1,‘sang‘,‘yu-a3i3i‘,1);
insert into vehicle_table(vehicle_id,vehicle_type,vehcile_num,driver_id) values(2,‘sang‘,‘yu-a3i3i‘,2);

5.
select v.vehicle_type, v.vehcile_num, d.driver_name, d.driver_sex from vehicle_table v left outer join driver_table d on v.driver_id=d.flowid;

作业：1.练习多个表之间的增删改成，
      2.设计你的项目，利用讲的原则
      3.每个组设计一个数据库文档(数据库设计说明书)

      
自练 /*by myself*/
create table student
(
    id int,
    name varchar2(8)
);

create table course
(
    id int,
    cname varchar2(8)
);

drop table student;
drop table course;
      
insert into student(id,name) values(1,‘张三‘);
insert into student(id,name) values(2,‘李四‘);
insert into student(id,name) values(3,‘王五‘);

insert into course(id,cname) values(1,‘足球‘);
insert into course(id,cname) values(2,‘音乐‘);
insert into course(id,cname) values(4,‘美术‘);
/* 左连接 */
select * from student left join course on student.ID=course.ID;

insert into student(id,name) values(1,‘huiny‘);

insert into course(id,cname) values(1,‘tuny‘);
/*右连接*/
select * from student right join course on student.ID=course.ID;
/*完全外连接*/
select * from student full join course on student.ID=course.ID;
/*内连接*/
select * from student inner join course on student.ID=course.ID;
select student.id,student.name,course.cname from student inner join course on student.ID=course.ID;
/*交叉连接*/
select * from student cross join course;
select * from student cross join course where student.ID=course.ID;

/*链接：http://www.dedecms.com/knowledge/data-base/sql-server/2012/0709/2872.html */

select s.Name,C.Cname from student_course as sc left join student as s on s.Sno=sc.Sno left join course as c on c.Cno=sc.Cno;

查询不重复记录 
select distinct id from student;
select distinct name from student;

order by 排序 /*默认从小到大排序*/
select *from student order by id;

update 使用
update student set name=‘huhu‘ where id=1;

显示所有表
select * from all_tables;

/***************************2015/07/20***************************/
1.创建表空间(oracle放表的地方)/*表空间名：account */
create tablespace account datafile ‘c:/account.dbf‘ size 25M;

2.创建用户(与表空间绑定)/*用户名:account 密码:account 用户空间:account */
create user account identified by account default tablespace account;

3.用户授权
grant resource,connect to account; /*授权*/

/**创建自己的表空间**/
create tablespace huiny datafile ‘c:/huiny.dbf‘ size 25M;
create user huhu identified by huhu default tablespace huiny;
grant resource,connect to huhu;