php - 如何正确运行需要大量处理的查询而不会出错

Question

我正在使用 Laravel 5.8 开发在线电子学习网站，我需要运行查询以更新已参加考试的用户的考试结果。

这是更新考试成绩的 Controller 方法:

public function compute($oleId)
    {
        try {
            ini_set('memory_limit', '-1');
            set_time_limit(0);

            DB::beginTransaction();

            /* Get the Exam */
            $exam = OlympiadExam::query()->where('ole_id', $oleId)->first();

            /* Calculate the score of Exam */
            if ($exam->ole_is_main == '0') {
                foreach ($exam->olympiadExamExecution as $execution) {
                    $questions = $execution->load('olympiadExamExecutionQuestion.olympiadExamQuestion');
                    $all = $exam->ole_question_count;
                    $notAnswered = $questions->olympiadExamExecutionQuestionNotAnswered->where('oee_oex_id', $execution->oex_id)->count();
                    $answered = $all - $notAnswered;
                    $truthy = $questions->olympiadExamExecutionQuestionTruthy->where('oee_oex_id', $execution->oex_id)->count();
                    $falsy = $all - ($truthy + $notAnswered);

                    $score = (float)($truthy - ($falsy / 3));
                    $percentage = (float)((($truthy * 3) - $falsy) / ($all * 3)) * 100;

                    $prePositive = (float)$percentage * ($exam->ole_percent_effect / 100);
                    $percentPositive = ($prePositive > 0) ? $prePositive : 0;
                    $percentFinal = (($percentage + $percentPositive) > 100) ? 100 : ($percentage + $percentPositive);
                    $scoreFinal = ((($percentFinal * $all) / 100) > $all) ? $all : ($percentFinal * ($all / 100));

                    $examResult = [
                        'oex_correct_answer_count' => $truthy,
                        'oex_wrong_answer_count' => $falsy,
                        'oex_no_answer_count' => $notAnswered,
                        'oex_score' => $score,
                        'oex_percent' => $percentage,
                        'oex_percent_positive' => $percentPositive,
                        'oex_percent_final' => $percentFinal,
                        'oex_score_final' => $scoreFinal,
                    ];

                    OlympiadExamExecution::query()->where('oex_id', $execution->oex_id)->update($examResult);
                }
            }

            $candidates = OlympiadExamExecution::query()->where('oex_ole_id', $oleId)->pluck('oex_percent_final')->toArray();
            if (!empty($candidates)) {
                $this->computeRank($candidates);
            }
            DB::commit();
            session()->flash('computeStatus', 'Process for calculating score completed');
            return redirect()->back();
        } catch (\Exception $exception) {
            DB::rollBack();
            session()->flash('computeStatus', 'Process for calculating score is going wrong');
            return redirect()->back();
        }

    }

现在，此方法适用于参加过考试的少数用户，但不适用于大量用户(大约 500 名用户)。

因此我尝试在查询运行之前设置 ini_set('memory_limit', '-1'); 和 set_time_limit(0); 但仍然没有锻炼并显示此消息:

所以我想知道是什么问题导致了这个错误？

我怎样才能正确地使这个处理适用于大量用户？

我非常感谢你们的任何想法或建议，因为我的生活取决于此...

Answer 1

在laravel中有一个chunk方法用于对大数据进行排队。您可以分块数据并尝试导入数据这是供引用的链接:here

希望此链接对您有所帮助。以下是有关文档的内容。

If you need to work with thousands of database records, consider using the chunk method provided by the DB facade. This method retrieves a small chunk of results at a time and feeds each chunk into a closure for processing. For example, let's retrieve the entire users table in chunks of 100 records at a time: