Laravel 5 查询生成器左连接

Question

我想在 laravel

中执行以下 mysql 命令

SELECT stars.*, SUM(points.amount) AS total_points
FROM stars
LEFT JOIN points ON stars.id = points.star_id 
GROUP BY stars.id

所以我写道：

\DB::table('stars')
            ->leftJoin('points', 'stars.id', '=', 'points.star_id')
            ->select(\DB::raw("stars.*, SUM('points.amount') AS total_points"))
            ->groupBY('stars.id')
            ->get();

当我转储并取消结果时，我看到 total_points 是 0.0。怎么了？

Answer 1

可能是引号的问题？

->select(\DB::raw("stars.*, SUM('points.amount') AS total_points"))

正确：

->select(\DB::raw("stars.*, SUM(points.amount) AS total_points"))

简单变体：

->selectRaw('stars.*, SUM(points.amount) AS total_points')

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