http://uk3.php.net/mysql_query
请注意，您从中学习的任何资源都可能已经过时了。 mysql_query 现已弃用。
http://uk3.php.net/manual/en/ref.pdo-mysql.php 是替代品。
这是我不久前写的使用 PDO 的入门指南（这更安全）。
在 php 脚本需要访问您的数据库时包含此文件。一个示例文件名是“database.php”，但这是您的电话。将命名空间从“yourproject”设置为您的项目被调用的任何内容。更正数据库凭据以适合您的数据库
希望这会为您省去很多麻烦！
我在底部为您提供了一些示例用法。我记得当我刚开始时，有时很难得到明确的建议。
//***** in a database class file*****/
namespace yourproject;
class Database {
private $db_con = '';
/*** Function to login to the database ***/
public function db_login()
{
// Try to connect
try{
// YOUR LOGIN DETAILS:
$db_hostname = 'localhost';
$db_database = 'yourdatabasename';
$db_username = 'yourdatabaseusername';
$db_password = 'yourdatabasepassword';
// Connect to the server and select database
$this->db_con = new \PDO("mysql:host=$db_hostname;dbname=$db_database",
"$db_username",
"$db_password",
array(\PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
// Prevent emulation of prepared statements for security
$this->db_con->setAttribute(\PDO::ATTR_EMULATE_PREPARES, false);
$this->db_con->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
return true;
}
// If it fails, send user to maintenance page
catch(PDOException $e)
{
header("location:http://yourwebsiteurl.com/maintenance.php");
exit();
}
}
/*** Function for database control ***/
public function db_control($query , $parameters, $returnID = false)
{
if(!is_array($query) && is_array($parameters))
{
try{
//prepare the statement
$statement = $this->db_con->prepare($query);
//execute the statement
$statement->execute($parameters);
//check whether this is a select, if it is then we need to retrieve the selected data
if(strpos($query, 'SELECT') !== false)
{
//fetch the results
$result = array();
while( $row = $statement->fetch(\PDO::FETCH_ASSOC) )
{
$result[] = $row;
}
//count the results
$count = count($result);
//return the array
return array( 'results' => $result, 'result_count' => $count );
}
//else return the number of affected rows
else{
//count the affected rows and place into a returnable array
$affected_rows = $statement->rowCount();
$returnArray = array('result_count' => $affected_rows);
//check to see if we are to return a newly inserted autoincrement ID from an INSERT
if($returnID)
{
//find the newly created ID and add this data to the return array
$insertID = $this->db_con->lastInsertId();
$returnArray['ID'] = $insertID;
}
return $returnArray;
}
}
catch(PDOException $e)
{
return false;
}
}
else{
return false;
}
}
}
// Start the database class and connect to the database then create a globally accessible function for ease of reference
$db = new \yourproject\Database();
$db->db_login();
function _db( $sql , $params , $returnID = false ){
return $GLOBALS['db']->db_control( $sql , $params , $returnID );
}
当您包含此文件时，您现在拥有一个新功能：_db()。由于该函数是全局函数，因此可以从任何类或 std 文件中调用它。当调用如下所示的变量时，将产生一个如下所示的数组：
array(
'result_count' => 3,
'results' => array(
array(/*row 1*/),
array(/*row 2*/),
array(/*row 3*/),
.. etc etc
)
)
现在在你的 php 脚本中包含你的数据库文件：
//call in the database file
require_once 'database.php';
//your query as in the op
$sql = 'SELECT * FROM pupil';
//your params for the query
$params = array();
//running the query and getting the results returned into a variable called $query
$query = _db($sql,$params);
//if no results
if( $query['result_count'] == 0 )
{
echo 'sorry no pupils in the system';
}
else
{
//looping through each result and printing into a html table row
for( $i = 0 ; $i < $query['result_count'] ; ++$i )
{
echo '<tr><td><a href="profile.php?id=' . $query['results'][$i]['pupil_id'] . '"</a></td>';
echo '<td>'. $query['results'][$i]['pupil_name'] . '</td>';
echo '<td>'. $query['results'][$i]['class_id'] . '</td></tr>';
}
}
您的原始查询，但传递了一些参数
//Passing parameters to the query
//your query
$sql = 'SELECT * FROM pupil WHERE pupil_id = :pupil_id AND class_id = :class_id';
//your params for the query
$params = array(
':pupil_id' => 12,
':class_id' => 17,
);
//running the query and getting the results returned into a variable called $query
$query = _db($sql,$params);
//deal with the results as normal...
如果将第三个参数设置为 true，则可以返回刚刚输入的行的自动 id，例如：
//where $sql is a query that will INSERT a row
$query = _db($sql,$params, true);