it_kbsu_ru/core/it_employee.php

<?php

class ITEmployeeComtroller extends DBProvider
{
    private $_connect_db;

    function __construct()
    {
        $this->_connect_db = parent::connect();
    }

    // public function get_all()
    // {
    //     $query = "SELECT * FROM it_employee;";
    //     $stmt = $this->_connect_db->prepare($query);
    //     $stmt->execute();
    //     return $stmt->fetchAll(PDO::FETCH_CLASS, "ITDeportament");
    // }


    public function get_employee_by_deportament($id_deportament)
    {
        $query = "SELECT 
            ie.id,
            ie.fio,
            ip.name as `position`,
            ie.phone 
        from it_employee ie 
        inner join it_position ip on ip.id = ie.id_position 
        WHERE ie.id_deportament =:id_deportament ORDER BY ip.id;";

        $stmt = $this->_connect_db->prepare($query);
        $stmt->bindParam("id_deportament", $id_deportament, PDO::PARAM_INT);
        $stmt->execute();
        return $stmt->fetchAll(PDO::FETCH_CLASS, "ITEmployeeToDeportament");
    }
}

class ITEmployeeToDeportament
{
    public $id, $fio, $position, $phone;
}