mysql中一些常用的指令

1.SQL簡介：Structured Query Language結構化查詢語言

DQL:資料查詢語言

DCL:資料控制語言

DML:資料操作語言

TPL :事物處理語言

DDL:資料定義語言

CCL:事物控制語言

2.資料定義語言

create database mysql1 character set gbk;本地編碼

create database mysql1 character set gbk collate gbk_chinese_ci;帶校對

drop databases 資料庫名；删除資料庫

alter table 表名 add image blob;增加表中的列

alter tabla 表名 modify job varchar(10);修改字元長度

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;修改字元集utf8

3.簡單查詢語言

select * form; 查詢所有的資訊

select name, age from 表名;查詢個别的資訊

select distinct english from student;過濾表中重複的資料

where查詢

<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查詢支援運算表達式

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查詢

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.資料操作語言

update user set salary=500;

update user set salary=300 where name="";

delete from user where name="";

delete from user;

使用truncate删除整張表中的記錄

truncate user;(摧毀整張表，重建整張表)