PHP 自学教程之MySQL数据库
PHP访问MySQL数据库的一般步骤： 1、连接MySQL数据库：使用mysql_connect()函数建立与MySQL服务器的连接。 2、选择MySQL数据库：使用mysql_select_db()函数选择MySQL数据库服务器上对于的数据库。 3、执行SQL语句：在选择的数据库中使用mysql_query（）函数
PHP访问MySQL数据库的一般步骤：
1、连接MySQL数据库：使用mysql_connect()函数建立与MySQL服务器的连接。
2、选择MySQL数据库：使用mysql_select_db()函数选择MySQL数据库服务器上对于的数据库。
3、执行SQL语句：在选择的数据库中使用mysql_query（）函数执行SQL语句。
4、关闭结果集：数据库操作完毕后，通过mysql_free_result()函数，释放MySQL系统资源。
5、关闭MySQL服务器：在完成数据库操作，应该使用mysql_close()函数关闭与数据库服务器连接。
PHP连接MySQL数据库实例代码：
<?php //定义连接数据库相关变量
$dbhost ="localhost" ;
$dbuser = "swxm"; // 我的用户名
$dbpass = "swxm"; // 我的密码
$dbname = "shopping"; // 我的mysql库名
//连接到数据库函数---mysql_connect
$connection=mysql_connect($dbhost,$dbuser,$dbpass);
if(!$connection){
die("无法连接到MySQL数据库:</br>".mysql_error());//诊断连接错误
}
//选择数据库函数--------mysql_select_db
$db_selecct=mysql_select_db($dbname, $connection);
if(!$db_selecct)
{
die("无法连接到指定的数据库".mysql_error());
}
$query="select * from user ";//构建查询语句
//执行SQL查询函数-----------mysql_query
$result=mysql_query($query);
if(!$result)
{
die("无法进行相关查询操作".mysql_error());
}
//查询结果
while($result_row=mysql_fetch_row($result))//取出结果并显示
{
$num=$result_row[0];
$age=$result_row[1];
$name=$result_row[2];
echo "<tr>";
echo "<td>$num</td>
<br>";
echo "<td>$age</td>
<br>";
echo "<td>$name</td>";
echo "</tr>";
}
?>结果展示：
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