public function safeDown()
 {
     CommentableDbManagerHelper::dropTables('petition', $this);
     RateableDbManagerHelper::dropTables('petition', $this);
     $this->dropTable('petition');
 }
 public function safeDown()
 {
     CommentableDbManagerHelper::dropTables('election', $this);
 }
 public function safeDown()
 {
     RateableDbManagerHelper::dropTables('candidate', $this);
     CommentableDbManagerHelper::dropTables('candidate', $this);
 }
 public function down()
 {
     CommentableDbManagerHelper::dropTables('file', $this);
     CommentableDbManagerHelper::dropTables('video', $this);
 }