use xuexiao;

create table studentInfo(
    name varchar(10),
    sex char, 
    age int, 
    address varchar(20)
);

show tables;
-- 插入操作
-- 值需要按照字端的顺序一一对应，如果插入的值顺序和创建表顺序相同，则字段可以省略
insert into studentInfo(`name` , sex , age ,address) values ("里斯",'男',19,'河南许昌');
insert into studentInfo(sex,address,age,name) values("女",'山东菏泽曹县',28,"笨比");
insert into studentInfo values ("宋江",'男',50,'菏泽曹县');
select * from studentInfo;

-- 修改已创建的表字段默认值
alter table studentInfo change sex sex char default'男';

insert into studentInfo(`name` , sex , age ,address) values ("潘金莲",'女',19,'山东菏泽');
insert into studentInfo(sex,address,age,name) values("女",'山东菏泽曹县',28,"王婆");
insert into studentInfo values ("西门庆",'男',50,'菏泽曹县');  -- 有默认值 如果省略字段，则值需要全写
select * from studentInfo;

create table studentInfo2(
    id int auto_increment primary key,
    name varchar(10),
    sex char, 
    age int, 
    address varchar(20)
);

show tables;
insert into studentInfo2(id,`name` , sex , age ,address) values (1,"牛逼",'男',666,'山东菏泽曹县');
insert into studentInfo2(`name` , sex , age ,address) values ("牛逼",'男',666,'山东菏泽曹县');
insert into studentInfo2(id,`name` , sex , age ,address) values (3,"牛逼2",'男',666,'山东菏泽曹县');
insert into studentInfo2(id,`name` , sex , age ,address) values (2,"牛逼3",'男',666,'山东菏泽曹县');
insert into studentInfo2(`name` , sex , age ,address) values ("窝里宝贝",'男',666,'山东菏泽曹县'),
    ("李逵",'男',30,'山东'),
    ("宋江",'男',30,'山东郓城'),
    ("吴用",'男',30,'山东石碣村'),
    ("鲁智深",'男',30,'山东五台山'),
    ("公孙胜",'男',30,'山东梁山');
    desc studentInfo2;
    select * from studentInfo2;
    select * from studentInfo;
    insert into studentInfo(`name` , sex , age ,address) values ("窝里宝贝",'男',666,'山东菏泽曹县'),
    ("李逵",'男',30,'山东'),
    ("宋江",'男',30,'山东郓城'),
    ("吴用",'男',30,'山东石碣村'),
    ("鲁智深",'男',30,'山东五台山'),
    ("公孙胜",'男',30,'山东梁山');
    

```sql
insert into studentInfo2 values (10,"窝里宝贝",'牛逼',666,'山东菏泽曹县'),
(11,"李逵",'男',30,'山东'),
(12,"宋江",'男',30,'山东郓城'),
(13,"吴用",'男',30,'山东石碣村'),
(14,"鲁智深",'男',30,'山东五台山'),
(15,"公孙胜",'男',30,'山东梁山');

select * from studentInfo2;

-- 修改
-- 修改指定的数据
update studentInfo set name = "潘金莲" where name = "笨比";
-- 没有写条件，则修改全部的数据
update studentInfo set name = "潘金莲";

-- 删除 delete from table where ...
delete from studentInfo2 where name = "牛逼2"; -- 删除符合条件的数据
delete from studentInfo; -- 删除所有数据

-- 销毁数据 不留下日志 ，速度快，无法恢复
truncate table studentInfo2;
```