Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)
Representiert eine Verbindung zwischen PHP und einem Datenbankserver.
PDO::getAvailableDrivers is the only PDO static method so it needs a double colon. The other PDO methods are used by an object, so they should use the -> syntax.
* PDO->beginTransaction — Initiates a transaction
* PDO->commit — Commits a transaction
* PDO->__construct — Creates a PDO instance representing a connection to a database
* PDO->errorCode — Fetch the SQLSTATE associated with the last operation on the database handle
* PDO->errorInfo — Fetch extended error information associated with the last operation on the database handle
* PDO->exec — Execute an SQL statement and return the number of affected rows
* PDO->getAttribute — Retrieve a database connection attribute
* PDO::getAvailableDrivers — Return an array of available PDO drivers
* PDO->lastInsertId — Returns the ID of the last inserted row or sequence value
* PDO->prepare — Prepares a statement for execution and returns a statement object
* PDO->query — Executes an SQL statement, returning a result set as a PDOStatement object
* PDO->quote — Quotes a string for use in a query.
* PDO->rollBack — Rolls back a transaction
* PDO->setAttribute — Set an attribute
Here is an singleton PDO example:
###### config.ini ######
db_driver=mysql
db_user=root
db_password=924892xp
[dsn]
host=localhost
port=3306
dbname=localhost
[db_options]
PDO::MYSQL_ATTR_INIT_COMMAND=set names utf8
[db_attributes]
ATTR_ERRMODE=ERRMODE_EXCEPTION
############
<?php class Database {
private static $link = null ;
private static function getLink ( ) {
if ( self :: $link ) {
return self :: $link ;
}
$ini = _BASE_DIR . "config.ini" ;
$parse = parse_ini_file ( $ini , true ) ;
$driver = $parse [ "db_driver" ] ;
$dsn = "${driver}:" ;
$user = $parse [ "db_user" ] ;
$password = $parse [ "db_password" ] ;
$options = $parse [ "db_options" ] ;
$attributes = $parse [ "db_attributes" ] ;
foreach ( $parse [ "dsn" ] as $k => $v ) {
$dsn .= "${k}=${v};" ;
}
self :: $link = new PDO ( $dsn, $user, $password, $options ) ;
foreach ( $attributes as $k => $v ) {
self :: $link -> setAttribute ( constant ( "PDO::{$k}" )
, constant ( "PDO::{$v}" ) ) ;
}
return self :: $link ;
}
public static function __callStatic ( $name, $args ) {
$callback = array ( self :: getLink ( ), $name ) ;
return call_user_func_array ( $callback , $args ) ;
}
} ?>
<?php // examples
$stmt = Database :: prepare ( "SELECT 'something' ;" ) ;
$stmt -> execute ( ) ;
var_dump ( $stmt -> fetchAll ( ) ) ;
$stmt -> closeCursor ( ) ;
?>
"And storing username/password inside class is not a very good idea for production code."
Good idea is to store database connection settings in *.ini files but you have to restrict access to them. For example this way:
my_setting.ini:
[database]
driver = mysql
host = localhost
;port = 3306
schema = db_schema
username = user
password = secret
Database connection:
<?php
class MyPDO extends PDO
{
public function __construct($file = 'my_setting.ini')
{
if (!$settings = parse_ini_file($file, TRUE)) throw new exception('Unable to open ' . $file . '.');
$dns = $settings['database']['driver'] .
':host=' . $settings['database']['host'] .
((!empty($settings['database']['port'])) ? (';port=' . $settings['database']['port']) : '') .
';dbname=' . $settings['database']['schema'];
parent::__construct($dns, $settings['database']['username'], $settings['database']['password']);
}
}
?>
Database connection parameters are accessible via human readable ini file for those who screams even if they see one PHP/HTML/any_other command.
Keep in mind, you MUST NOT use 'root' user in your applications, unless your application designed to do a database maintenance.
And storing username/password inside class is not a very good idea for production code. You would need to edit the actual working code to change settings, which is bad.
<?php
class PDOConfig extends PDO {
private $engine;
private $host;
private $database;
private $user;
private $pass;
public function __construct(){
$this->engine = 'mysql';
$this->host = 'localhost';
$this->database = '';
$this->user = 'root';
$this->pass = '';
$dns = $this->engine.':dbname='.$this->database.";host=".$this->host;
parent::__construct( $dns, $this->user, $this->pass );
}
}
?>
Diese Seite bei php.net