"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.
Die Klasse PDO
(PHP 5 >= 5.1.0, PHP 7, PHP 8, PECL pdo >= 0.1.0)
Einführung
Repräsentiert eine Verbindung zwischen PHP und einem Datenbankserver.
Klassenbeschreibung
Inhaltsverzeichnis
- PDO::beginTransaction — Startet eine Transaktion
- PDO::commit — Bestätigt eine Transaktion
- PDO::__construct — Erzeugt eine PDO-Instanz, die eine Datenbankverbindung darstellt
- PDO::errorCode — Ruft den SQLSTATE-Code ab, der mit der letzten Operation über das Datenbank-Handle verknüpft ist
- PDO::errorInfo — Ruft die erweiterten Fehlerinformationen ab, die mit der letzten Operation über das Datenbank-Handle verknüpft sind
- PDO::exec — Führt ein SQL-Statement aus und liefert die Anzahl der betroffenen Zeilen
- PDO::getAttribute — Ruft ein Attribut einer Datenbankverbindung ab
- PDO::getAvailableDrivers — Liefert ein Array mit den verfügbaren PDO-Treibern
- PDO::inTransaction — Prüft, ob es eine offene Transaktion gibt
- PDO::lastInsertId — Liefert die ID der zuletzt eingefügten Zeile oder den Wert der zuletzt eingefügten Sequenz
- PDO::prepare — Bereitet eine Anweisung zur Ausführung vor und liefert ein Anweisungsobjekt
- PDO::query — Bereitet eine SQL-Anweisung ohne Platzhalter vor und führt sie aus
- PDO::quote — Setzt eine Zeichenkette für die Verwendung in einer Abfrage in Anführungszeichen
- PDO::rollBack — Macht eine Transaktion rückgängig (Rollback)
- PDO::setAttribute — Setzt ein Attribut
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User Contributed Notes 8 notes
Megaloman ¶
15 years ago
williambarry007 at gmail dot com ¶
13 years ago
PDO and Dependency Injection
Dependency injection is good for testing. But for anyone wanting various data mapper objects to have a database connection, dependency injection can make other model code very messy because database objects have to be instantiated all over the place and given to the data mapper objects.
The code below is a good way to maintain dependency injection while keeping clean and minimal model code.
<?php
class DataMapper
{
public static $db;
public static function init($db)
{
self::$db = $db;
}
}
class VendorMapper extends DataMapper
{
public static function add($vendor)
{
$st = self::$db->prepare(
"insert into vendors set
first_name = :first_name,
last_name = :last_name"
);
$st->execute(array(
':first_name' => $vendor->first_name,
':last_name' => $vendor->last_name
));
}
}
// In your bootstrap
$db = new PDO(...);
DataMapper::init($db);
// In your model logic
$vendor = new Vendor('John', 'Doe');
VendorMapper::add($vendor);
?>
sinri at everstray dot com ¶
6 years ago
For some Database Environment, such as Aliyun DRDS (Distributed Relational Database Service), cannot process preparing for SQL.
For such cases, the option `\PDO::ATTR_EMULATE_PREPARES` should be set to true. If you always got reports about "Failed to prepare SQL" while this option were set to false, you might try to turn on this option to emulate prepares for SQL.
Anonymous ¶
7 years ago
I personnaly create a new instance of PDO like this :
$dbDatas = parse_ini_file( DB_FILE );
$dbOptions = [
\PDO::ATTR_DEFAULT_FECTH_MODE => \PDO::FETCH_OBJ,
\PDO::ATTR_ERRMODE => \PDO::ERRMODE_EXCEPTION
];
$dsn = sprintf( 'mysql:dbname=%s;host=%s', $dbDatas['dbname'],
$dbDatas['host'] );
$this->cn = new \PDO( $dsn, $dbDatas['user'], $dbDatas['password'],
$dbOptions );
$this->cn->exec( 'SET CHARACTER SET UTF8' );
anrdaemon at freemail dot ru ¶
16 years ago
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.
thz at plista dot com ¶
11 years ago
Starting with PHP 5.4 you are unable to use persistent connections when you have your own database class derived from the native PDO class. If your code uses this combination, you will encounter segmentation faults during the cleanup of the PHP process.
You can still use _either_ a derived PDO class _or_ persistent connections.
For more information, please see this bug report: https://bugs.php.net/bug.php?id=63176
kcleung at kcleung dot no-ip dot org ¶
14 years ago
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 ( ) ;
?>
