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HomeDatabaseMysql Tutorialmysql学习笔记--第1天_MySQL

1、像网页上的账户、图片、文章都是存在数据库里面
2、Oracle 、DB2 、SQL server等等多钟数据库
PHP中选择使用mysql PHP+mysql黄金搭档
PHP和mysql都是开源的,免费实用,配置性好。
mysql中小型适合,但没有Oracle强大。
3、mysql的架构:C/S client/server
在server端开启,client端操作
mysql DBMS(DB代表数据库 M代表管理 S代表系统)
客户端操作 服务器端---数据库--数据表--(行(记录),行(字段))
4、程序员要学的mysql
1、为你的项目设计表
2、使用sql语句(sql编程--连接,数据增删改查)
可以使用工具完成。
5、mysql安装,和php整合
目录结构:my.ini配置文件 :自己修改端口、字符集等等

启动服务器:(1)自带启动入口(2)计算机管理/服务/找到mysql服务一项可以启动
(3)用cmd命令启动:net strat/stop/restrat mysql 启动服务
linux环境下 是service mysqld strat
配置环境变量:计算机属性搭配环境变量path。吧对应的目录放在path的变量值里面
路径之间用分号隔开。在cmd命令行下先在里面的路径查找该命令
6、数据库sql的语句操作
SQL (structured Query language)
DDL创建表
DML数据操作 增删改查
DQL数据查询
DCL数据控制语句(管理权限,数据更改)
1、执行sql语句,链接到数据库服务器
cmd命令:mysql -h(地址)IP地址/本机:localhost -u(指定用户) root -p123456(密码)
提示mysql>进入 exit退出
要留一个管理员用户
DDL:
create database liangcha(库名称)
drop database liangcha (删除库)(相当于新建删除文件夹)
create database if not exists liangcha
create table liangcha user(id int,name char);
选择一个库作为默认数据库,方便操作
use liangcha;
show database/table;(查看)
DML:
insert into user(id,name) values
updata user set name='lili' where id='1' (修改把id为1的那个名字修改为lili)
delete from user where id=‘1’ (删除) where=操作的条件
DQL:
select * from user(查询表)
DCL:
/s看状态
show databases 看所有库
show tables 看所有表
desc 看表结构
show varlable 配置文件中的变量

 



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