Answers for "foreign key in laravel 8 migration file"

make a forign key in migrations using laravel 8

$table->unsignedBigInteger('user_id');
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');

foreign key laravel migration

$table->foreign('column_name')->references('id')->on('table_name')->onDelete('cascade');

add foreign key column laravel 5.8

update your `integer('user_id')` to `bigInteger('user_id')`
public function up() { 
        Schema::create('evaluation', function (Blueprint $table) { 
            $table->increments('id'); 
            $table->bigInteger('user_id')->unsigned()->index(); 
            $table->timestamps();
            $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
        });
    }

Laravel create foreign key column in migration

$table->foreignId('post_id')
                ->constrained()
                ->onUpdate('cascade')
                ->onDelete('cascade');