Eloquent chunk() missing half the results

Question

I have a problem with Laravel\'s ORM Eloquent chunk() method. It misses some results. Here is a test query :

$destinataires = Destinataire::where(\'statut\', \'&         


        

Answer 1

Quick answer: Use chunkById() instead of chunk().

The explanation can be found in the Laravel documentation:

When updating or deleting records inside the chunk callback, any changes to the primary key or foreign keys could affect the chunk query. This could potentially result in records not being included in the chunked results.

Here is the solution example:

DB::table('users')->where('active', false)
    ->chunkById(100, function ($users) {
        foreach ($users as $user) {
            DB::table('users')
                ->where('id', $user->id)
                ->update(['active' => true]);
        }
    });

If you are updating database records while chunking results, your chunk results could change in unexpected ways. So, when updating records while chunking, it is always best to use the chunkById method instead. This method will automatically paginate the results based on the record's primary key.

(end of the update)

The original answer:

I had the same problem - only half of the total results were passed to the callback function of the chunk() method.

Here is the code which had problems:

Transaction::whereNull('processed')->chunk(100, function ($transactions) {
    $transactions->each(function($transaction){
        $transaction->process();
    });
});

I used Laravel 5.4 and managed to solve the problem replacing the chunk() method with cursor() method and changing the code accordingly:

foreach (Transaction::whereNull('processed')->cursor() as $transaction) {
    $transaction->process();
}

Even though the answer doesn't address the problem itself, it provides a valuable solution.