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今天在连表获取数据的时候，老是获取不到想要的，确实有点无力适从的感觉。
归根到底，还是对laravel不够熟悉，至少是数据库操作那块。
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问题是这样的：
我想要通过连表中间表，拿中间表的id。但是product 在关联的中间表中有多个，需要brandId,categoryId去限制获取，然后就可以获取到，但是我实际操作的时候却不是想要的结果。
获取的是categoryId=50 ，brand_id=1 的所有商品，还有需要中间表的id
array:10 [▼0 => array:21 [▼"id" => 323 "name" => "" "snumber" => "" "number" => 0 "product_categories" =>
0 => array:6 [▼ "id" => 20 "product_id" => 323 "category_id" => 2 "brand_id" => 1 "created_at" => "2017-04-17 13:16:42" "updated_at" => "2017-04-17 13:16:42" ] 1 => array:6 [▼ "id" => 458 "product_id" => 323 "category_id" => 1 "brand_id" => 1 "created_at" => "2017-04-17 15:40:34" "updated_at" => "2017-04-17 15:40:34" ] 2 => array:6 [▼ "id" => 758 "product_id" => 323 "category_id" => 50 "brand_id" => 1 "created_at" => "2017-04-17 17:21:30" "updated_at" => "2017-04-17 17:21:30" ] 3 => array:6 [▼ "id" => 991 "product_id" => 323 "category_id" => 47 "brand_id" => 1 "created_at" => null "updated_at" => null ] ]
] 1 => array:21 [▶] 2 => array:21 [▶] 3 => array:21 [▶] 4 => array:21 [▶] 5 => array:21 [▶] 6 => array:21 [▶] 7 => array:21 [▶] 8 => array:21 [▶] 9 => array:21 [▶] ]
我只想要的是product_categories 中的第2个数组就行
方法是：
$productIds = ProductCategories::where('category_id', $categoryId)
->where('brand_id', $brandId)
->pluck('product_id', 'id')
->all();
$products = Product::whereIn('id', $productIds)
->with('productCategories')
->whereHas('productCategories', function ($q1) use ($categoryId, $brandId) {
return $q1->where(['brand_id' => $brandId,'category_id' => $categoryId]);
})
->get();
发现这样操作并不行。。。
搞好久还是老实的去看文档
$productIds = ProductCategories::where('category_id', $categoryId)
->where('brand_id', $brandId)
->pluck('product_id', 'id')
->all();
$products = Product::whereIn('id', $productIds)
->with(['productCategories' => function ($q1) use ($categoryId, $brandId){ $q1->where(['brand_id' => $brandId ,'category_id' => $categoryId]); }]) ->get();
结果就可以了：
array:10 [▼ 0 => array:21 [▼ "id" => 323 "name" => "" "snumber" => "" "number" => 0
"product_categories" => array:1 [▼ 0 => array:6 [▼ "id" => 758 "product_id" => 323 "category_id" => 50 "brand_id" => 1 "created_at" => "2017-04-17 17:21:30" "updated_at" => "2017-04-17 17:21:30" ] ] ]