Laravel Eloquent: Show Parent with Comma-Separated Relationship Values

In reports or tables, you often need to show one record with all its "children" records on the same line, separated by a comma. In this tutorial, I will show you TWO ways to achieve that in Laravel.

Let's imagine you have a relationship of Player -> hasMany -> Game with a score for each game.

players table:

games table:

Your task is to show all the players with all their scores separated by a comma. Something like this table:

Or, in a Laravel Collection form:

Illuminate\Database\Eloquent\Collection {#2285
    all: [
      App\Models\Player {#2287
        name: "First player",
        scores: "5,8",
      },
      App\Models\Player {#2284
        name: "Second player",
        scores: "10,3,5",
      },
    ],
  }

I will show you a few ways.

Option 1. Collection methods: pluck() and implode()

Controller:

$players = Player::with('games')->get();

Blade:

@foreach ($players as $player)
    <tr>
        <td>{{ $player->name }}</td>
        <td>{{ $player->games->pluck('score')->implode(',') }}</td>
    </tr>
@endforeach

As you can see, the pluck() method forms the Collection of just score column values, and then implode() transform the Collection into a comma-separated string.

You could improve the performance by loading only the relationship fields that you actually need:

$players = Player::with('games:player_id,score')->get();

But, in terms of performance, there's a better way.

Option 2. MySQL: GROUP_CONCAT() method

Why load all the relationship rows/columns and make the Collection work if we can ask the database to group that for us?

Here's the Query Builder raw query utilizing MySQL:

$players = Player::query()
  ->selectRaw('players.name, GROUP_CONCAT(games.score) as scores')
  ->join('games', 'players.id', '=', 'games.player_id')
  ->groupBy('players.name')
  ->get();

Then, in Blade:

@foreach ($players as $player)
    <tr>
        <td>{{ $player->name }}</td>
        <td>{{ $player->scores }}</td>
    </tr>
@endforeach

The GROUP_CONCAT() function uses a comma as the default separator, but you can customize it, read the official MySQL documentation for all the options.