MySQLi class

<?php

/* Config */
const DB_HOST = 'localhost';
const DB_USER = 'root';
const DB_PASS = '';
const DB_NAME = 'testDb';
const DB_CHARSET = 'utf8';

const DEBUG = 1;

/* New DB instance */
$db = new DB();

/* Test variables */
$id = 1;
$something = "456";

/* Prepared statement */
$query = 'SELECT * FROM `test1` WHERE `id` = ? AND `something` = ?';
$sql = $db->query(
    $query,
    array($id, $something)
);

/* Normal query */
$query = 'SELECT * FROM `test2` WHERE `id` = 1';
$sql = $db->query($query);

/* Fetch data */
$data = $db->fetch_all();

/* Display result */
print_r($data);

/* Close db */
$db->close();


/**
 * MySQLi db class by Andrew Larsen
 */
class DB
{
    private $mysqli;
    private $stmt;
    private $lastPrepared;

    public function __construct($host = DB_HOST, $user = DB_USER, $pass = DB_PASS, $dbname = DB_NAME, $charset = DB_CHARSET){
        $this->mysqli = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);

        if (!$this->mysqli) {
            if (DEBUG)
                echo 'Code: ' . mysqli_connect_errno() . ' - Message: ' . mysqli_connect_error();

            return false;
        }

        $this->mysqli->set_charset(DB_CHARSET);
    }

    private function bind($parameters) {
        $param_type = '';
        $param_values = array();

        foreach ($parameters as $key => $value) {
            $param_values[] = $value;

            if (is_string($value))
                $param_type .= 's'; // string
            else if (is_int($value))
                $param_type .= 'i'; // int
            else if (is_float($value))
                $param_type .= 'd'; // double
            else
                $param_type .= 'b'; // blob and unknown
        }

        $params = array();

        /* with call_user_func_array, array params must be passed by reference */
        $params[] = &$param_type;

        for ($i = 0; $i < count($param_values); $i++) {
            /* with call_user_func_array, array params must be passed by reference */
            $params[] = &$param_values[$i];
        }

        call_user_func_array(array($this->stmt, 'bind_param'), $params);
    }

    private function prepare($query) {
        if (!$this->stmt = $this->mysqli->prepare($query)) {
            if (DEBUG)
                echo "Prepare failed: (" . $this->mysqli->errno . ") " . $this->mysqli->error;

            return false;
        }

        return true;
    }

    private function execute() {
        if (!$this->stmt->execute()) {
            if (DEBUG)
                echo "Execute failed: (" . $this->stmt->errno . ") " . $this->stmt->error;

            return false;
        }

        return true;
    }

    public function query($query, $parameters = array()) {
        if (is_array($parameters) && count($parameters) > 0) {
            $this->lastPrepared = true;

            if ($this->prepare($query) === false)
                return false;

            $this->bind($parameters);
            if ($this->execute() === false)
                return false;
        } else {
            $this->lastPrepared = false;

            if (!$this->stmt = $this->mysqli->query($query)) {
                if (DEBUG)
                    echo "Query failed: (" . $this->mysqli->errno . ") " . $this->mysqli->error;

                return false;
            }
        }

        return $this->stmt;
    }

    public function fetch_all($autoClean = true) {
        if ($this->lastPrepared) {
            $result = $this->stmt->get_result();
            $data = $result->fetch_all(MYSQLI_ASSOC);
        } else {
            $data = $this->stmt->fetch_all(MYSQLI_ASSOC);
        }

        if ($autoClean) {
            $this->stmt->free_result();

            if ($this->lastPrepared) $this->stmt->close();
        }

        if (count($data) == 1)
            return $data[0];

        return $data;
    }

    public function begin($option = 'MYSQLI_TRANS_START_READ_ONLY') {
        $options = array(
            'MYSQLI_TRANS_START_READ_ONLY',
            'MYSQLI_TRANS_START_READ_WRITE',
            'MYSQLI_TRANS_START_WITH_CONSISTENT_SNAPSHOT'
        );

        if (!in_array($option, $options))
            return false;

        $this->mysqli->begin_transaction($option);
    }

    public function commit() {
        $this->mysqli->commit();
    }

    public function autocommit($bool) {
        $this->mysqli->autocommit($bool);
    }

    public function close() {
        $this->mysqli->close();
    }

    public function stmtClose()
    {
        $this->stmt->close();
    }

}

?>