php - Laravel Eloquent find posts that has all the given tags

Question

Consider 3 tables as below

class Post extends Model
{
    public function tags()
    {
        return $this->belongsToMany(Tag::class, 'post_tags', 'post_id', 'tag_id');
    }

}

posts table

|id | title   |
+---+---------+
|1  |  post1  |
|2  |  post2  |
|3  |  post3  |
|4  |  post4  |

tags table

|id |  value  |
+---+---------+
|1  |  tag01  |
|2  |  tag02  |
|3  |  tag03  |
|4  |  tag04  |

post_tags table

|  post_id | tag_id  |
+----------+---------+
|     1    |    1    |
|     2    |    3    |
|     2    |    4    |
|     3    |    1    |
|     4    |    1    |
|     4    |    4    |

The only post that has both tag01 and tag04 is post with id = 4

But when I get posts with this code

Post::whereHas('tags', function($q) {
  $q->whereIn('tag_id', [1, 4]);
}

I get all the posts that has tag01 or tag04.

I want to get Posts where have both tag01 and tag02 in its tags relation.

How can I achieve this result using Eloquent or if it's not possible using QueryBuilder

标签： phplaraveleloquenthas-and-belongs-to-many

Answer 1

我认为您可以使用多个 where 条件

 Post::whereHas('tags', function($q) {
       $q->where('tag_id', 1);
   
    })->whereHas('tags', function($q) {
       $q->where('tag_id', 4);
   
    })->get();

如果 id 是动态的，那么

$id=[1,4];
    Post::where(function($query)use($id){
        foreach ($id as $value){
            $query->whereHas('tags',function ($query)use($value){

                $query->where('tag_id',$value);


            });
        }


    })->get();