Order by AVG on a tagging system.

try

$batsmens = $tag->batsmen->sortByDesc(function ($item) { return $item->reviews->max('rating'); });

@foreach($batsmens  as $batsmen)

@endforeach

Ive tried this and it just returns the batsmen like usual but the order by highest avg rating part does not seem to work

I don't think I know enough to get you from where you are to where you're going, but maybe I can help along the path.

To get an average 'rating' with normal SQL select the average column and then you would use Group By clause and then to order it by descending order, use the Order By clause. For example:

SELECT b.name, avg('r.rating') 
FROM batsmen b
LEFT INNER JOIN batsmen_tag bt ON bt.Tag_id = b.batsmen_id
LEFT INNER JOIN reviews r ON r.Batsmen_id = bt.batsmen_id
GROUP BY b.name
ORDER BY avg(r.rating) desc

Now all you have to do is translate your SQL into Eloquent calls for Laravel (or you can always use Raw Expressions). Something like this, maybe:

$batsmen = DB::('batsmen')
    ->leftJoin('batsmen_tag', 'batsmen.id', '=', 'batsmen_tag.batsmen_id')
    ->leftJoin('reviews', 'batsmen.id', '=', 'reviews.batsmen_id')
    ->select('DB::raw('avg('reviews.rating') as rating, batsmen.name'))
    ->groupBy('batsmen.name')
    ->orderBy('rating', 'desc')
    ->get();

Here are a couple other resources that may help:

https://stackoverflow.com/questions/44661388/how-to-order-by-an-average-rating

https://laracasts.com/discuss/channels/eloquent/orderby-computed-related-attribute

https://laravel.io/forum/03-01-2014-use-avg-in-eloquent-for-orderby

Thanks for the replies so far, ive tried those suggested and none of them work. Some more information on this, i can pull back batsmen and order by highest average i do this like this