MySQL数据库的基本知识大全

以下的文章主要介绍的是MySQL数据库的基本知识，其中包括对MySQL数据库的创建，以及对一些相关的数据类型描述，其中还涉及到表的创建，以下就是文章的详细内容描述，望你会有所收获。 MySQL数据库安装 最好改变字符集UTF8 创建数据库 createdatabasemydata;

以下的文章主要介绍的是MySQL数据库的基本知识，其中包括对MySQL数据库的创建，以及对一些相关的数据类型描述，其中还涉及到表的创建，以下就是文章的详细内容描述，望你会有所收获。

MySQL数据库安装 最好改变字符集UTF8

创建数据库

<ol class="dp-xml"><li class="alt"><span><span>create database mydata;  </span></span></li><li><span>use mydata; </span></li></ol>

数据类型 int double char varchar datetime longtext

创建表 create table dept

<ol class="dp-xml"><li class="alt"><span><span>(  </span></span></li><li><span>deptno int primary key,  </span></li><li class="alt"><span>dname varchar(14),  </span></li><li><span>loc varchar(13)  </span></li><li class="alt"><span>);  </span></li><li class="alt"><span>create table emp  </span></li><li><span>(  </span></li><li class="alt"><span>empno int primary key,  </span></li><li><span>ename varchar(10),  </span></li><li class="alt"><span>job varchar(15),  </span></li><li><span>mgr int,  </span></li><li class="alt"><span>hiredate datetime,  </span></li><li><span>sal double,  </span></li><li class="alt"><span>deptno int,  </span></li><li><span>foreign key (deptno) references dept(deptno)  </span></li><li class="alt"><span>);  </span></li></ol>

MySQL数据库执行脚本文件.sql \. 文件路径 或 source 文件路径

？

sql文件中 — 注释

MySQL管理软件 MySQL administrator,toad for MySQL

查看数据库 show databases;

查看表 show tables;

查看表结构 desc dept;

插入数据

<ol class="dp-xml"><li class="alt"><span><span>intsert into dept values(1,'a','a');  </span></span></li><li><span>commit; </span></li></ol>

分页 select * from dept order by deptno desc limit 3,2; （从第三条往后数两条）

自增 create table article

<ol class="dp-xml"><li class="alt"><span><span>(  </span></span></li><li><span>id int primary key auto_increment,  </span></li><li class="alt"><span>title vachar(255)  </span></li><li><span>);  </span></li><li class="alt"><span>insert into article values(null,'a');  </span></li><li><span>insert into article(title) values('c'); </span></li></ol>

日期处理

获取当前日期 select now();

转化字符串 select date_format(now(),’%Y-%m-%d %H:%i:%s’);

<ol class="dp-xml"><li class="alt"><span>jdbc连接MySQL  </span></li><li><span>Connection </span><span class="attribute">conn</span><span>=</span><span class="attribute-value">null</span><span>;  </span></li><li class="alt"><span>Statement </span><span class="attribute">stmt</span><span>=</span><span class="attribute-value">null</span><span>;   </span></li><li><span>ResultSet </span><span class="attribute">rs</span><span>=</span><span class="attribute-value">null</span><span>;   </span></li><li class="alt"><span>try{   </span></li><li><span>Class.forName("com.</span>MySQL<span>.jdbc.Driver").newInstance();  </span></li><li class="alt"><span class="attribute">conn</span><span>=</span><span class="attribute-value">DriverManager</span><span>.getConnection("jdbc:</span>MySQL<span>://localhost/test? </span><span class="attribute">user</span><span>=</span><span class="attribute-value">root</span><span>&</span><span class="attribute">password</span><span>=</span><span class="attribute-value">root</span><span>");  </span></li><li><span class="attribute">stmt</span><span>=</span><span class="attribute-value">conn</span><span>.createStatement();  </span></li><li class="alt"><span class="attribute">rs</span><span> = </span><span class="attribute-value">stamt</span><span>.executeQuery(sql);  </span></li><li><span>}  </span></li><li class="alt"><span>catch(Exception e){}  </span></li><li><span>finally{  </span></li><li class="alt"><span><strong>本文来源gao@daima#com搞(%代@#码网</strong>try{  </span></li><li><span>if(rs!=null){rs.close; </span><span class="attribute">rs</span><span>=</span><span class="attribute-value">null</span><span>;}  </span></li><li class="alt"><span>if(stat!=null){stat.close; </span><span class="attribute">stat</span><span>=</span><span class="attribute-value">null</span><span>;}  </span></li><li><span>if(conn!=null){conn.close; </span><span class="attribute">conn</span><span>=</span><span class="attribute-value">null</span><span>;}  </span></li><li class="alt"><span>}  </span></li><li><span>catch(SQLException e){  </span></li><li class="alt"><span>e.printStackTrace();  </span></li><li><span>}  </span></li><li class="alt"><span>}  </span><span> </span></li></ol>

以上的相关内容就是对MySQL数据库知识的介绍，望你能有所收获。

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