如何在laravel中连接两个表？

Question

I am new to Laravel. I am having a difficulty in joining two tables (User Table and Transaction Table). Below are codes from TransactionController.

public function index()
{
    $user = User::all();
    $transactions = $user->transactions;
    $transaction = array();

    foreach ($transactions as $row) {
        array_push($transaction,
        [
            'id' => $row->id,
            'name' => $row->user->name,
        ]
        );
    }

    return response() -> json ([
        'transaction' => $transaction,
    ]);
}

I would like to print all users' name and all transactions in the Postman. I manage to print all users' name but when I tried to join with Transaction table, I am facing an error. I already tried left join method as below:

$user = User::all() 
  ->select('user.id','user.name')
  ->join('transactions','transactions.id','=','user.id')
  ->get();

  foreach ($transactions as $row) {
        array_push($transaction,
        [
            'id' => $row->id,
            'name' => $row->user->name,
        ]
        );
    }

    return response() -> json ([
        'transaction' => $transaction,
    ]);
}

Is there any way to join two tables in laravel? Thank you.

Answer 1

Assuming you have this relationship in your User model.

public function transactions() {
  return $this->hasMany('App\Transaction', 'user_id');
}

And in your Transaction model

public function user() {
  return $this->belongsTo('App\User', 'user_id');
}

Now, to fetch users together with their transactions

$users = User::with('transactions')->get();

If you want to fetch transactions inline with user

 $data = Transaction::with('user')->get();

 $transactions = collect($data)->map(function ($transaction){
    return [
        'id' => $transaction->id,
        'name' => $transaction->user->name,
        'total' => $transaction->total,
    ];
});