Laravel 在 withCount 方法上使用 where 子句

Question

I am trying to do a where clause on withCount method of laravel's eloquent query builder using this piece of code.

$posts = Post::withCount('upvotes')->where('upvotes_count', '>', 5)->get();

and this code is giving me this error.

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'upvotes_count' in 'where clause' (SQL: select , (select count( ) from upvotes where upvotes . upvoteable_id = posts . id and upvotes . upvoteable_type = App\\Post) as upvotes_count from posts where upvotes_count > 5)

So from what I can guess is that upvotes_count isn't selected and hence the column is not being found, BUT if I execute this piece of code.

$posts = Post::withCount('upvotes')->get();

Then I am getting this output.

{
"id": 1,
"user_id": 15,
"title": "Voluptatum voluptas sint delectus unde amet quis.",
"created_at": "2016-10-07 13:47:48",
"updated_at": "2016-10-07 13:47:48",
"upvotes_count": 7
},
{
"id": 2,
"user_id": 2,
"title": "Molestiae in labore qui atque.",
"created_at": "2016-10-07 13:47:48",
"updated_at": "2016-10-07 13:47:48",
"upvotes_count": 2
},

Which basically means that upvotes_count is being selected, hence i am really confused about how to solve this problem.

(More options that I tried so far are given below with the respective error associated to it.)

$posts = Post::where('id', $id)->withCount(['upvotes' => function($query) {
        $query->where('upvotes_count', '>', 5);
    }])->get();

error.

SQLSTATE[42S22]: Column not found: 1247 Reference 'upvotes_count' not supported (forward reference in item list) (SQL: select , (select count( ) from upvotes where upvotes . upvoteable_id = posts . id and upvotes . upvoteable_type = App\\Post and upvotes_count > 5) as upvotes_count from posts where id = 1)

code.

$posts = Post::where('id', $id)->with(['upvotes' => function($query) {
        $query->select('upvoteable_id AS upvotes_count');
    }])->where('upvotes_count', '>', 5)->get();

AND

$posts = \App\Post::where('id', $id)->with(['upvotes' => function($query) {
        $query->selectRaw('upvoteable_id AS upvotes_count');
    }])->where('upvotes_count', '>', 5)->get();

error.

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'upvotes_count' in 'where clause' (SQL: select * from posts where id = 1 and upvotes_count > 5)

---

I just want to use where clause on a count() method which is in a relationship with a parent model.

Answer 1

You can achieve requested result by using:

$posts = Post::withCount('upvotes')
         ->having('upvotes_count', '>', 5)
         ->get();

Answer 2

another good way to do this we can filter that separately and even assign an alias to that column name

$posts = Post::withCount([
    'upvotes', 
    'upvotes as upvotes_count' => function ($query) {
        $query->where('upvotes_count', '>', 5);
    }])
    ->get();

Now in blade you can do

$posts->upvotes_count

Answer 3

我不确定这是否在您提出问题后实施，但您现在可以这样做

$posts = Post::has('upvotes','>',5)->get();

Answer 4

I think using has() is the best solution:

Post::has('upvotes','>',5)->withCount('upvotes')->get()

You could also use a filter:

Post::withCount('upvotes')->get()->filter(function($post) { return $post->upvotes_count > 5; })

You could also disable strict mode in config/database.php (probably not a good idea)

'strict' => false,

Post::withCount('upvotes')->having('upvotes_count','>',5)->get()

You could also try to add a groupBy clause (using having in strict mode), but this will likely require you to include every column in your table (due to 'ONLY_FULL_GROUP_BY'), which could break things if you ever add another column to your table, and probably won't work anyway because I think you need to include 'upvotes_count' in the groupBy and it seems to be a non grouping field.

Answer 5

I ran into the same problem, and tried the same things you did. I'm guessing there is a way to replicate the SQL generated by the withCounts call but add a way to make xxx_counts available to a where clause, but I just filtered the resulting collection instead.

$allTags = Tag::withCount('articles')->get();

$usedTags = $allTags->filter(function ($value, $key) {
        return $value->articles_count > 0;
    });

Answer 6

If you need to select only rows that the counter is greater than or equal to 1 you can try the following code:

$posts = Post::withCount('upvotes')
             ->havingRaw('upvotes_count')
             ->get();

I don't know if this is the best solution but it's an alternative. Another alternative would be get the posts and use array filter as mentioned in a comment above.