数据类型

1，正数类型测试：tinyint,int

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2,字符串类型

1 char ,varchar

1,创表
create table vc (
v varchar(4),
c char(4));
2,插入数据
insert into vc values('a','a');
insert into vc values('ab ','ab ');
3,查询数据
select * from vc;
select length(v),length(c) from vc;

2，枚举型

1创表
create table student3(
name varchar(50),
sex enum('m','f'),
hobby set('music','book','game','disc') );
2插入数据
insert into student3 values ('tom','m','book,game');
3查询
select * from student3;

3，集合类型

1创表
create table student3(
name varchar(50),
sex enum('m','f'),
hobby set('music','book','game','disc') );
2插入数据
insert into student3 values ('tom','m','book,game');
3查询
select * from student3;

3时间和日期类型

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4，浮点型

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2.掌握精准小数decimal类型
1创表
create table test5(decimal_test decimal(5,2));
2插入数据
insert into test5 values (70.245);
3查询结果
select * from test5;