Souke/console/migrations/m161227_130138_champs_date_derniere_connexion.php

<?php

use yii\db\Migration;
use yii\db\Schema;

class m161227_130138_champs_date_derniere_connexion extends Migration
{
    public function up()
    {
        $this->addColumn('user', 'date_derniere_connexion', Schema::TYPE_DATETIME) ;
    }

    public function down()
    {
        $this->dropColumn('user', 'date_derniere_connexion') ;
    }
}