$pdo helper class

ez_db.php

<?php // require initialize $pdo from outside

  class EzDb {
    // init pdo function
    public static function init_pdo($host, $db_name, $user, $pass){
      global $pdo;
      return new PDO(
        "mysql:host=$host;dbname=$db_name;charset=utf8",
        $user,
        $pass,
        array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8")
      );
    }
    // execute, fetch functions
    public static function exec($sql, $params=array(), $die_flag=False){
      global $pdo;
      $stm = $pdo->prepare($sql);
      $result = $stm->execute($params);
      if($result){
        return array(
          'success' => true,
        );
      }
      else {
        if($die_flag){
          die(self::extract_err($stm));
        }
        return array(
          'success' => false,
          'error'   => self::extract_err($stm),
        );
      }
    }
    public static function fetchAll($sql, $params=array(), $die_flag=False){
      global $pdo;
      $stm = $pdo->prepare($sql);
      $result = $stm->execute($params);
      if($result){
        return array(
          'success' => true,
          'data'    => $stm->fetchAll(PDO::FETCH_ASSOC),
        );
      }
      else {
        if($die_flag){
          die(self::extract_err($stm));
        }
        return array(
          'success' => false,
          'error'   => self::extract_err($stm),
        );
      }
    }
    public static function fetch($sql, $params=array(), $die_flag=False){
      global $pdo;
      $stm = $pdo->prepare($sql);
      $result = $stm->execute($params);
      if($result){
        return array(
          'success' => true,
          'data'    => $stm->fetch(PDO::FETCH_ASSOC),
        );
      }
      else {
        if($die_flag){
          die(self::extract_err($stm));
        }
        return array(
          'success' => false,
          'error'   => self::extract_err($stm),
        );
      }
    }
    // utility function
    function extract_err($stm){
      return print_r($stm->errorInfo(), true);
    }
  }

?>