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Counting total distant relationships in Laravel (eager loading?)

I'm having issues getting a proper count total with my Laravel model.

Model Structure

  • User
  • Item
  • ItemLike

A user can have multiple Items, and each of these Items can have multiple ItemLikes (when a user 'likes' the item).

I can easily get the individual ItemLike counts when using an Item model:

return $this->itemLikes()->count();

But I can't figure out how to get the total # of ItemLike's a User has across all the Item's he owns.

EXAMPLE

User A has 3 Items. Each Item has 5 ItemLike's, for a grand total of 15.

I tried using eager loading on the User model like this:

return $this->items()->with('itemlikes')->get()->count();

But that returns 3 (the # of Items)

These are the queries it ran, which appears like the second query is the one I want, yet every way I try it I still get 3 instead of 15

select * from `items` where `items`.`user_id` = '1000'
select * from `item_likes` where `item_likes`.`item_id` in ('1000', '1001', '1002')

After suggestions from others I found 2 solutions to get the result.

Using whereIn:

$itemViewCount = ItemView::
whereIn('item_views.item_id', $this->items()->lists('id'))
->count();

return $itemViewCount;

2 queries for a total of 410μs

Using join:

$itemViewCount = $this->items()
->join('item_views', 'item_views.item_id', '=', 'items.id')
->count();

return $itemViewCount;

2 queries for a total of 600μs

Isn't it just a case of creating a method that would return the number of items for the model. eg:

#UserModel
public function nbLikes()
{
    $nbLikes = 0;
    foreach($this->items() as $item) {
        $nbLikes += $item->itemLikes()->count();
    }

    return $nbLikes;
}

And then User::nbLikes() should return the piece of data you are looking for?

试试这个:$ query =“从item_likes il,item itm中选择count(il.id),其中il.item_id = itm.id和tm.user_id = 1000”;

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