Question

我是laravel的新手，我只是想知道是否有任何方法可以有效地重写此代码？

$answer1 = SurveyAnswer::where('answer_1','=','1')->get()->count();
$answer2 = SurveyAnswer::where('answer_1','=','2')->get()->count();
$answer3 = SurveyAnswer::where('answer_1','=','3')->get()->count();
$answer4 = SurveyAnswer::where('answer_1','=','4')->get()->count();
$answer5 = SurveyAnswer::where('answer_1','=','5')->get()->count();

Answer 1

首先获取数据：

#include "opencv2/core/core.hpp"
#import "opencv2/highgui/cap_ios.h"

UIImage* MatToUIImage(const cv::Mat& image);
void UIImageToMat(const UIImage* image,
                     cv::Mat& m, bool alphaExist = false);

然后使用加载的集合计算答案：

$answers = SurveyAnswer::whereIn('answer_1', [1, 2, 3, 4, 5])->get();

此代码只生成一个数据库查询，而不是五个。

Answer 2

试试这个：

$matches = [1,2,3,4,5];

$answer = SurveyAnswer::whereId('answer_1', $matches)->groupBy('answer_1')->get();

Answer 3

您可以使用带有case表达式的agregate函数轻松完成此操作，因为mysql不支持本机透视函数以下是一个示例，并尝试根据您的要求重写并直接对数据库进行处理，如果有效，则可以将其与laravel raw sql一起使用。

 select id,
 sum(case when value = 1 then 1 else 0 end) ANSWER1_COUNT,
 sum(case when value = 2 then 1 else 0 end) ANSWER2_COUNT
from survey
group by answer

一次写多个laravel查询

3 个答案: