MySQL基本用语!初学者必看!

1.SQL简介:Structured Query Language结构化查询语言
DQL:数据查询语言
DCL:数据控制语言
DML:数据操作语言
TPL :事物处理语言
DDL:数据定义语言
CCL:事物控制语言
2.数据定义语言
create database mysql1 character set gbk;本地编码
create database mysql1 character set gbk collate gbk_chinese_ci;带校对
drop databases 数据库名;删除数据库
alter table 表名 add image blob;增加表中的列
alter tabla 表名 modify job varchar(10);修改字符长度
alter table 表名 drop image;删除表
rename table 表名 to user;改表名字
alter table 表名 character set utf8;修改字符集utf8
3.简单查询语言
select * form; 查询所有的信息
select name, age from 表名;查询个别的信息
select distinct english from student;过滤表中重复的数据
where查询
<1>.select name chinese math english from student where name=”“;
<2>.select name chinese math english from student where english>90;
<3>.select * from student where(chinese+math+english)>200;
<4>where查询支持运算表达式
1.select * from student where english between 80 and 90
2.select * from student where math in(89,90,91);
3.select * from student where name like ‘李%’;
4.select * from student where math>90 and chinese>80;
<5>order查询
1.select * from student order by math;
2.select * from student order by (++) desc;
3.select name math from student where name like ‘李%’;
4.数据操作语言
update user set salary=500;
update user set salary=300 where name=”“;
delete from user where name=”“;
delete from user;
使用truncate删除整张表中的记录
truncate user;(摧毁整张表,重建整张表)!

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转载自blog.csdn.net/lulubaby_/article/details/78734192