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Hi i am using PDO DB class to connect to database. But i really wonder if i am doing it correct or not. All connection set up is fine but i get error when i run a query
My Directory Structure is
/root
/dbops <-- Directory contains `config.php` -->
/dbfunctions <-- Directory contains `DBclass.php` & `DBFuncts.php` -->
Now contents of config.php
are:
define( 'DB_HOST', 'localhost' );
define( 'DB_USERNAME', 'root');
define( 'DB_PASSWORD', '');
define( 'DB_NAME', 'testDB');
define('DB_CHAR', 'utf8');
function __autoload($class){
$parts = explode('__', $class);
$path = implode(DIRECTORY_SEPARATOR,$parts);
require_once $path . '.php';
}
DBclass.php
contains:
class dbdunctions__DBclass{
public $instance = null;
public function __construct() {}
final private function __clone() {}
public static function instance()
{
if (self::$instance === null)
{
$opt = array(
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES => TRUE,
PDO::ATTR_STATEMENT_CLASS => array('myPDOStatement'),
);
$dsn = 'mysql:host='.DB_HOST.';dbname='.DB_NAME.';
charset='.DB_CHAR;
self::$instance = new PDO($dsn, DB_USERNAME, DB_PASSWORD,
$opt);
}
return self::$instance;
}
public static function __callStatic($method, $args) {
return call_user_func_array(array(self::instance(), $method), $args);
}
}
class myPDOStatement extends PDOStatement
{
function execute($data = array())
{
parent::execute($data);
return $this;
}
}
DBFuncts.php
contains below:
class dbfunctions__DBFuncts
{
protected $_con;
public function __construct()
{
$db = new dbfunctions__DBclass();
$this->_con = $db->con;
}
function gotodb(array $data){
$result =
$this->_con::instance()->prepare($qry)->execute(array(/*parameters*/));
}
}
Now when query is fired with $result
then i get following error
Parse error: syntax error, unexpected '::' (T_PAAMAYIM_NEKUDOTAYIM) in dbops/dbfunctions/DBFuncts.php on line 12
Please guide. I have already spent 2 hrs on this issue and googling around.
</div>
Instead of
$this->_con::instance()
You should be able to just do
$this->_con->instance()->prepare($qry)->execute(array(/*parameters*/));
Not sure if it's a typo for when you put the code in - but I did notice that in the DBclass.php you have class dbdunctions__DBclass - surely this should be class dbfunctions__DBclass() ?
Also there seems to be some other errors in your example code ... But lets tackle them one at a time :)
Try adjusting this way. I have it working on my server with some adjustments. Notably instantiating the connection in the __construct()
of the dbdunctions__DBclass()
class and assigning $this->_con
to the self::$instance
(dbdunctions__DBclass::$instance;
):
class dbdunctions__DBclass
{
// Make the instance static
public static $instance = null;
public function __construct()
{
// Create the static connection in the construct
$this->init();
}
private function init()
{
if (self::$instance === null) {
$opt = array(
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
PDO::ATTR_EMULATE_PREPARES => TRUE,
PDO::ATTR_STATEMENT_CLASS => array('myPDOStatement'),
);
self::$instance = new PDO('mysql:host='.DB_HOST.';dbname='.DB_NAME.'; charset='.DB_CHAR, DB_USERNAME, DB_PASSWORD, $opt);
}
}
final private function __clone()
{
}
public static function __callStatic($method, $args)
{
return call_user_func_array(array(self::instance(), $method), $args);
}
}
class myPDOStatement extends PDOStatement
{
public function execute($data = array())
{
parent::execute($data);
return $this;
}
}
class dbfunctions__DBFuncts
{
protected $_con;
public function __construct()
{
// Create instance of database
$database = new dbdunctions__DBclass();
// Assign the connection to the $this->_con
$this->_con = dbdunctions__DBclass::$instance;
}
public function gotodb($statement = false,$bind = false)
{
// Incase the statement or bind is empty, return 0
if(empty($statement) || empty($bind))
return 0;
// Create the query with method chain
$query = $this ->_con->prepare($statement)
->execute($bind);
// Fetch results
while($row = $query->fetch())
$result[] = $row;
// If results return array else return 0 for consistency
return (!empty($result))? $result : 0;
}
}
// Instantiate
$dbFunc = new dbfunctions__DBFuncts();
// Use whatever you use to return a result here. This statement happens
// to work for my database...but likely not yours
print_r($dbFunc->gotodb("select * from `users` where `ID` = :ID",array(":ID"=>"29")));
class dbfunctions__DBFuncts
{
protected $_con;
public function __construct()
{
$db = new dbfunctions__DBclass();
$this->db = $db;
}
function gotodb(array $data){
$result =
$stmt = $this->db->prepare($qry);
$stmt->execute(array(/*parameters*/));
}
The PDO object gets created then made into a "member object". The gotodb object uses the "member object" PDO instance. Below is a sample of code from a site I'm working on which should help explain it better:
try {
$sql="
SELECT
id
, name
, description
FROM
ue_bug_project
";
// $stmt objected created by preparing the SQL query for execution, using the PDO object, which in this case is $this->db
$stmt = $this->db->prepare($sql);
// The execute method of the $stmt object is run executing the query, in this case no query data is bound as there is no user submitted data being used
$stmt->execute();
// The result set is grabbed in one hit and placed into the projects array (I really should have set up the $projects variable as an empty array beforehand)
$projects = $stmt->fetchAll(PDO::FETCH_ASSOC);
return $projects;
}
// If the query fails with an error, the catch block is run, in this case i log the error.
catch (PDOException $e) {
error_log('Error when getting the list of projects!');
error_log(' Query with error: '.$sql);
error_log(' Reason given:'.$e->getMessage()."
");
return false;
}
}
From the looks of your code there's probably no real need to place your own wrapper around the PDO class