laravel foreign key constraint
public function up()
{
Schema::create('replies', function (Blueprint $table) {
$table->bigIncrements('id');
$table->text('body');
$table->unsignedBigInteger('question_id');
$table->integer('user_id')->unsigned();
$table->foreign('question_id')->references('id')->on('questions')->onDelete('cascade');
$table->timestamps();
});
}