Wrapper class for SQL database connections. Helper methods for fetching, adding, editing and deleting data.

SQLDB.php

<?
class DB {
    private static $conn = null;
    public static function connect($host="localhost", $user="root", $pass=null, $db=null) {
        DB::$conn = mysqli_connect($host, $user, $pass, $db);
    }
    public static function insert($table, $data) {
        if (!DB::$conn) {
            DB::connect();
        }
        $rows = array_keys($data);
        $vals = array_values($data);
        foreach ($vals as $i => $val) {
            switch (gettype($val)) {
                case "integer":
                case "double":
                case "boolean":
                    $vals[$i] = (string) $val;
                    break;
                case "string":
                    $vals[$i] = "\"" . $val . "\"";
                    break;
            }
        }
        $result = mysqli_query(DB::$conn, "INSERT INTO `" . $table . "` (`" . implode("`, `", $rows) . "`) VALUES (" . implode(", ", $vals) . ");");
        return $result;
    }
    public static function fetch($table, $where=null) {
        if (!DB::$conn) {
            DB::connect();
        }
        $result = mysqli_query(DB::$conn, "SELECT * FROM `" . $table . "`" . ($where ? " WHERE " . $where : "") . ";");
        $data = array();
        if ($result) {
            $count = 0;
            while ($row = mysqli_fetch_assoc($result)) {
                $data[] = $row;
                $count++;
            }
        }
        return $data;
    }
    public static function error() {
        return mysqli_error(DB::$conn);
    }
}
?>