Question

这样的MySQL查询：

SELECT a.id, a.name, b.TotalMeal, c.TotalCollection
FROM users a
LEFT JOIN (
    SELECT user_id, SUM( breakfast + dinner + lanch ) AS TotalMeal
    FROM meals
    GROUP BY user_id) b ON a.id = b.user_id
LEFT JOIN (
    SELECT user_id, SUM( amount ) AS TotalCollection
    FROM collections
    GROUP BY user_id) c ON a.id = c.user_id
LIMIT 0, 30

我想雄辩地将其转换为Laravel，但我感到困惑。我有三张桌子。例如-users（id，name，email ..），饭食（user_id，breakfast，lanch，dinner）和collections（user_id，amount）。

Answer 1

有一个小技巧，它使用withCount()选择可以在您的方案中使用的相关表的总和：

User::query()
    ->select([
        'id',
        'name',
    ])
    ->withCount([
        'meals as total_meals' => function ($query) {
            $query->select(DB::raw('SUM(breakfast + dinner + lunch)'));
        },
        'collections as total_collections' => function ($query) {
            $query->select(DB::raw('SUM(amount)'));
        },
    ])
    ->get();

在此查询中，withCount将为您执行联接。

如何将mysql转换为laravel雄辩的左联接？

1 个答案: