开始:触摸MySQL_MySQL
学习MySQL,少不了安装一个MySQL数据库,安装想必很简单,其实也是,我下载了一个MySQL5.7,百度了一下安装步骤,就安装成功了。相对于Oracle来说要简单不少。
买了两本书,看了《MySQL必知必会》,适合入门者。后面一部分学习过程将参考此书。虽然网络上有不少电子书,但是纸质书毕竟要好一些。下面开始。
1. 数据库基础
数据库目前理解起来其实就是表,表分为行和列,一个数据库可以有多个表,每个表记录一类信息,如一个表记录学生的成绩,一个表记录老师的课程,如果将学生成绩和老师的课程放到一个表里,感觉就比较奇怪。表中的每一列都需要有一个类型值,是存放数字,还是文本,长度有没有限制等。这些表的属性应该称之为为模式。着重强调一下是表中的每一行都需要有一个唯一的id,主要是方便后续的查找,修改等操作。
另外提到了SQL这种语言,由于我有C语言的基础,理解起来比较容易。SQL,用来操作数据库的语言。第一章看起来比较容易。
2.环境
环境搭建比较简单,该书对应的网站,提供了SQL脚本,创建了 供应商、产品目录、顾客列表和顾客订单列表。下载该脚本文件。在windows开始栏中,运行MySQL Command Line Client。输入密码即进入到了MySQL命令行。
a 创建一个名为lab的数据库:myslq> create database lab;
b 使用该数据库:mysql> use lab;
c 执行下载的脚本创建表:mysql> source G:/study/MySQL/mysql_scripts/create.sql;
d 执行下载的脚本插入值:mysql> source G:/study/MySQL/mysql_scripts/populate.sql
e 查看表vendors中的内容:myslq> select * from vendors;

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