Laravel ：使用 Eloquent 在查询中加入

Question

我有五个 table 需要从中获取数据。 post,product,categories,attributes,post_attribute

我的模型中有一个查询，它收集一个产品的所有 post，它包含类别和属性详细信息。 查询：

 Post::with(['product.categories.attributes'])->whereStatus("Active")->get();

回复：

 "PostDetails": [
    {
        "id": 153,
        "user_id": 3,
        "product_id": 1,
        "demand_or_supply": "Demand",
        "description": "This is a post description three",
        "image_one": null,
        "image_two": null,
        "image_three": null,
        "image_four": null,
        "status": "Active",
        "created_at": "2018-05-07 09:51:08",
        "updated_at": "2018-05-07 09:51:08",
        "product": {
            "id": 1,
            "title": "Diamond",
            "icon": null,
            "status": "Active",
            "created_at": "2018-04-27 18:46:28",
            "updated_at": "2018-04-27 18:46:28",
            "categories": [
                {
                    "id": 1,
                    "product_id": 1,
                    "title": "Shape",
                    "status": "Active",
                    "sort_order": 1,
                    "created_at": "2018-04-27 18:46:28",
                    "updated_at": "2018-04-27 18:46:28",
                    "attributes": [
                        {
                            "id": 1,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "Round",
                            "status": "Active",
                            "sort_order": 2,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 2,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "Princess",
                            "status": "Active",
                            "sort_order": 1,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 3,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "Oval",
                            "status": "Active",
                            "sort_order": 3,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 4,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "Kite",
                            "status": "Active",
                            "sort_order": 8,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 5,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "1-5",
                            "status": "Active",
                            "sort_order": 4,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 6,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "6-10",
                            "status": "Active",
                            "sort_order": 9,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 8,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "-2",
                            "status": "Active",
                            "sort_order": 10,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 9,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "+2 -4",
                            "status": "Active",
                            "sort_order": 7,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        },
                        {
                            "id": 10,
                            "product_id": 1,
                            "category_id": 1,
                            "parent_id": null,
                            "title": "+4 -6 1/2",
                            "status": "Active",
                            "sort_order": 6,
                            "created_at": "2018-04-27 18:46:29",
                            "updated_at": "2018-04-27 18:46:29"
                        }
                    ]
                },

在这个 table 中还有一个叫 post_attributes 的 table 我存储 attribute_id 和 product_id 属于 attribute 和 product table.

我想过滤 attributes 仅在 post_attributes table 中可用且仅适用于 'product' 的数据，在 post_attributes [=37] 中可用=] 与 product_id 和 attribute_id。 我该怎么做？

Answer 1

要约束预加载关系，您可以将闭包传递给预加载查询，要查询关系，您可以使用 whereHas 函数，所以它看起来像这样：

Post::with(['product.categories.attributes' => function($query) {
    // Eager load constraint
    $query->whereHas('post_attribute', function ($query) {
        $query->where('product_id', 1); // Filter by the joined data
    });
}])->whereStatus("Active")->get();

希望对您有所帮助。