xyzshop/helper/statistics/order_reader.php

<?php

namespace statistics;

use function PHPUnit\Framework\isNull;

class order_reader
{
    public function refill_vr_reader($cond,$order='refill_order.order_id asc')
    {
        $result = Model('')->table('refill_order,vr_order')
            ->field('min(refill_order.order_id) as min_oid,max(vr_order.order_id) as max_oid')
            ->join('inner')
            ->on('refill_order.order_id=vr_order.order_id')
            ->where($cond)
            ->find();
        $min_oid = $result['min_oid'];
        $max_oid = $result['max_oid'];

        if(is_null($min_oid) || is_null($max_oid)) {
            return false;
        }

        $start = intval($min_oid);
        while (true)
        {
            $cond['vr_order.order_id'] = ['egt', $start];
            $items = Model('')->table('refill_order,vr_order')
                ->field('*')
                ->join('inner')
                ->on('refill_order.order_id=vr_order.order_id')
                ->where($cond)
                ->limit(1000)
                ->order($order)
                ->select();

            if(empty($items)) {
                break;
            }

            foreach ($items as $item) {
                $start = intval($item['order_id']) + 1;
                yield $item;
            }
        }

        return true;
    }
}