How to foreign key in Laravel 5.3 - laravel

Question

I use Laravel 5.3 and MySQL
I will to make foreign key on Forums and references on user id
Migration in Users
{
Schema::create('users', function (Blueprint $table) {
$table->increments('id');
$table->string('name');
$table->string('email')->unique();
$table->string('password');
$table->string('api_token', 60)->unique();
$table->rememberToken();
$table->timestamps();
});
}
Migration in Forums
{
Schema::create('forums', function(Blueprint $table) {
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->string('thread');
$table->text('deskripsi');
$table->timestamps();
});
Schema::table('forums', function(Blueprint $table) {
$table->foreign('user_id')->references('id')->on('users');
});
}
But I get found error
SQLSTATE[23000]: Integrity constraint violation: 1452 Cannot add or update a child row: a foreign key constraint fails (`dbkelas`.`forums`, CONSTRAINT `forums_user_id_foreign` FOREIGN KEY (`user_id`) REFERENCES `users` (`id`)) (SQL: insert into `forums` (`thread`, `deskripsi`, `updated_at`, `created_at`) values (Matematika Diskrit, Bagaimana ya, 2017-01-14 15:10:18, 2017-01-14 15:10:18))
Do you have any solution?

Answer 1

I think your migration code need to update like:
Schema::create('forums', function(Blueprint $table) {
$table->increments('id');
$table->integer('user_id')->unsigned();
$table->foreign('user_id')
->references('id')
->on('users')
->onDelete('cascade');
$table->string('thread');
$table->text('deskripsi');
$table->timestamps();
});
Hope this work for you!