Getting rank of row in OrderBy desc Eloquent query, How can i make this query work in laravel 5.5 eloquents?)

问题

I am trying to give my users a ranking number for my Laravel hiscores pagination table.

This is the MySQL query I found working. I am trying to put make this work as a Laravel eloquent query.

select @i := @i + 1 ranking, t.*
from (select @i:=0) initvars, users t  ORDER BY wins DESC;

My Laravel eloquent query right now:

$ranking = User::orderBy('wins', 'DESC')->paginate(10);

Thanks in advance!

回答1:

A bit of a late response but I figured it out. This is my solution.

I First added this function to my User Modal Class.

public function getRanking(){
   $collection = collect(User::orderBy('wins', 'DESC')->get());
   $data       = $collection->where('id', $this->id);
   $value      = $data->keys()->first() + 1;
   return $value;
}

Now in my view I run my getRanking() function.

@foreach($ranking as $key => $rankings)
    <tr>
        <td>{{ $rankings->getRanking() }}</td>
        <td><a href="{{ route('profileView', ['id' => $rankings->id]) }}">{{ $rankings->username }}</a></td>
        <td>{{ $rankings->wins }}</td>
        <td>{{ $rankings->losses }}</td>
    </tr>
@endforeach

I am using my array keys to determine the user ranking.

Good night!

回答2:

$table = (new User)->getTable();
$select = \DB::raw("@i := coalesce(@i + 1, 1) ranking, {$table}.*")
$users = User::select($select)->orderByDesc('wins')->paginate(5);

In the above, you need to select table.* again because even if you use addSelect instead of select eloquent loses the original column selection. I'm not sure if it's a bug or intended behaviour, but i'll investigate.

To clarify, if you just do

$raw = \DB::raw("@i := coalesce(@i + 1, 1) ranking");
$model->addSelect($raw); // this way
$model->select($raw); // or this way

The only field you will see on your model is ranking.

What might be of note is that if you're paginating based on something which fluctuates like ranking you may see some unexpected behaviour. For example if page 1 shows users a, b, c, d, e (rank 1-5 respectively) and user f climbs the ranking to position 5 before the visitor clicks to page 2, they'd see user e (now rank 6) again and not see user f (now rank 5) when on page 2.

来源：https://stackoverflow.com/questions/47824688/getting-rank-of-row-in-orderby-desc-eloquent-query-how-can-i-make-this-query-wo

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php

mysql

laravel

laravel-5

laravel-eloquent