MySQL与php的连接操作要点
MySQL扩展库操作MySQL数据库的步骤如下:
1:获取连接.
2:选取书库。
3:设置操作编码。
4:发送SQL指令(MySQL数据库可以分为四种指令:
1:ddl: 数据定义语言。
2:dml:数据操语言(如CURD);
3:dql:数据查询语言。(如select)
4:dtl:数据事物语言。
)。
5:接收返回结果,并且处理。
6:断开连接。
具体的示例代码如下:
<pre name="code" class="php"><pre name="code" class="php"><pre name="code" class="php"><?php //1:连接数据库 $con=mysql_connect("localhost","root","toor"); //如果没有连接成功要报错 if(!$con){ echo "连接失败"; exit(); }//2: 选择要操作的数据库 mysql_select_db("test");//3:发送SQL指令 mysql_query("set names utf8");//设置查询编码 $sql="select *from test1"; $res=mysql_query($sql,$con);//4:返回结果(按行遍历返回) while($row=mysql_fetch_row($res)){ echo "$row[0]-------------$row[1]-----------$row[2]-----------$row[3]-----------$row[4]".'<br/>'; }//5:释放资源,关闭连接 mysql_free_result($res); mysql_close($con);?>
要说明的是,这里的所有的操作都是在内存的里面去操作的,不能想当然的就是什么东西,所以说,了解一些底层的东西还是有一定的好处的。

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