Question

public class Room {
  static belongsTo = [hotel:Hotel]
  Source source
  long sourceid
  RoomType type
  float price
  float oldPrice
  Currency currency
  boolean isShown = false
  boolean approved = false
  static hasMany = [roomTexts:RoomText]

  def beforeDelete () {
    Photos.withNewSession {
      Photos.findAllByRoom(this).each {photosInstance->
        photosInstance.delete()
      }
    }

    RoomFeatures.withNewSession {
      RoomFeatures.findAllByRoom(this).each {roomF->
        roomF.delete()
      }
    }
  }

}

Then:

def room = Room.get(1) 
room.delete()

Will throw com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException.

Cannot delete or update a parent row: a foreign key constraint fails (`prod_test`.`photos`, CONSTRAINT `FKC50C8881EC5F6358` FOREIGN KEY (`room_id`) REFERENCES `room` (`id`))

It happens because photos deletion session are not yet flushed into DB and Hibernate tries to delete Room entity, i think…

Here is room deletion code:

Room.withTransaction{status->
   roomInstance.delete(flush: true)
}

Is there any workaround or “right way” to resolve this problem ?

Of course i could manually delete all photos before deleting room but using beforeDelete helps to keep code clean and avoid code duplication.

Answer 1

Why can’t you have photos in the hasMany list along with RoomText, and make photos belong to Room?