<?php

namespace Qs\Db\Obj;

use Qs_Array;
use Qs_Db_Obj;

/**
 * Trait PreviousDataTrait
 * @package Qs\Db\Obj
 * @mixin Qs_Db_Obj
 */
trait PreviousDataTrait
{
    private $previousData = [];

    public function loadPreviousData()
    {
        if ($this->getPrimaryKey()) {
            $this->previousData = $this->_getFromDb($this->getPrimaryKey());
        }
    }

    public function getPreviousData($field = null, $default = null)
    {
        return Qs_Array::get($this->previousData, $field, $default);
    }
}