A simple Laravel job that can help you export data through CSV from a database with millions of rows.

CreateGeneralExportFileJob.php

<?php

namespace App\Jobs;

use App\Models\GeneralExport;
use Storage;


class CreateGeneralExportFileJob implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

    public $timeout = 1200;

    /**
     * Create a new job instance.
     *
     * @return void
     */
    public function __construct(
        private GeneralExport $export,
        private string $exportFileName,
        private int $page = 1,
    )
    {
        //
    }

    /**
     * Execute the job.
     *
     * @return void
     */
    public function handle()
    {
        $members = $this->getMembers();

        $columns = [
            'Member ID',
            'Full Name',
            'Phone Number',
            'Gender',
            'Date of Birth',
            'Email',
        ];

        $filesystemAdapter = Storage::disk('public');
        if($this->export->status === 'pending') {
            $fileName = 'general_exports/' . Carbon::now()->timestamp . '-' . $this->exportFileName . '-' . $this->export->user_id . '.csv';

            // add the headers only on the first run of this job... on subsequent runs, only append the data
            $filesystemAdapter->append($fileName, implode(',', $columns) . PHP_EOL);
        } else {
            $fileName = $this->exportFileName;
        }

        if($this->export->status !== 'processing') {
            $this->export->update([
                'status' => 'processing',
                'status_message' => "Job {$this->page} in export processing started"
            ]);
        } elseif($this->export->status === 'processing') {
            $this->export->update([
                'status_message' => "Job {$this->page} in export processing started"
            ]);
        }

        $fileResource = fopen($filesystemAdapter->path($fileName), 'a+');

        foreach ($members as $member) {
            fwrite($fileResource, implode(',', [
                    $member->id,
                    $member->user->first_name . ' ' . $member->user->last_name,
                    $member->user->phone,
                    $member->gender,
                    $member->dob,
                    $member->user->email,
                ]) . PHP_EOL);
        }

        fclose($fileResource);

        $nextPageUrl = $members->nextPageUrl();
        $nextPage = null;
        if(!is_null($nextPageUrl)) {
            $nextPage = explode('=', $nextPageUrl, 2)[1];
        }

        if(is_null($nextPage)) {
            // we are done processing
            $this->export->update([
                'status' => 'processed',
                'status_message' => 'Export file processed successfully and ready for download',
                'file' => $fileName,
            ]);
            return;
        }

        // refresh to get current state of export before using it for next job
        $this->export->refresh();

        dispatch(new static($this->export, $fileName, $nextPage));
    }


    public function getMembers() {
        return Member::paginate(10000, ['*'], 'page', $this->page)
    }

}

GeneralExport.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;

class GeneralExport extends Model
{
    use HasFactory;

    protected $fillable = ['user_id', 'status', 'file', 'status_message'];
}