Oracle 数据库sql基础练习

1. 连接数据库：

    sqlplus/nolog

2. 连接管理员:

    conn system/ok;

目的：有dba权限可以创建用户

3. 通过管理员创建用户:

       create user haha identified by ok;
           identified by :指定用户密码

4. 连接用户

        haha:conn haha/ok;  (失败)
       1.缺失登陆权限：create session

5. 登陆管理员给haha授予登陆权限

      1.conn system/ok;
      2.grant create session to haha;

6. 连接haha用户:

       conn haha/ok;

7. 创建表：

       create table student(id number(4),name varchar2(10)) 

8. 登录管理员

    conn system/123;

9. 授予haha用户建表权限

    grant create table to haha

10. 给用户haha分配内存大小

    alter user haha quota unlimited on users;

11. haha用户进行建表

    conn haha/123;
    create table student(id number(4),name varchar2(10));

12. 插入数据

    insert into student(id,name) values(1,'张三');

13. 授予dba权限

    conn system/123;
    grant dba to haha;

14. 修改haha的密码

    conn system/123;
    alter user haha identified by 1234;

15. 设置haha的密码过期

    conn system;
    alter user haha password expire;

16. 锁定与解锁账号

    alter user haha account lock;
    alter user haha account unlock;

17. 分页查询

    select d.* from (select p.*,Rownum r from person p)
    where r>(index-1)*size and r<=index*size;

18. 插入指定列

    insert into student(id,name) 
    values(2,'李四');

19. 插入不指定列

    insert into student
    values(3,'李四',to_date('2019-01-10','yyyy,mm,dd'),'02');


    insert into student
    values(3,'李四',to_date('2019-01-10 10:10:10','yyyy,mm,dd hh:mi:ss'),'02');

20. 修改数据

    update student set name='王五',birthday=sysdate
    where name='张三';

21. 删除数据

    delete from student
    where id=1;