Fixing the migration with Foreign Key instead of an Index

db/migrations/20181108145741_une_seule_adresse.php

@@ -41,7 +41,7 @@ class UneSeuleAdresse extends AbstractMigration
         $this->execute('TRUNCATE TABLE adresses;');
 
         // Add a unique index on user_id
-        $table->addIndex(['user_id'], ['unique' => true])
+        $table->addForeignKey('user_id', 'users', 'id', ['delete' => 'CASCADE'})
             ->removeColumn('alias')
             ->save();