Question

I have two Person and PersonDTO classes and I’m using NHibernate to save these objects. As while as I have One user there is no problem and as soon as another user is going to update the object that another user is updating it. then Both of the can update the same object and because it is updated by another user, on of the changes will lost.

In order to implement cuncurrency I used two ways that both of them faced with problem.

• The first solution : Use the Person constructor to update the object
• The second approach : Using a GetByID method

The first approach is working great with any problem but unfortunately I don’t have enough permition to the Load Person completetly with its dependencies. so that I have to use the second approach.

In the second approach when I set (update) Version it is o up to the last second, but NHibernate is using its old Version so that my changes won’t apply.

Look at the following Code

load a Person by ID

person = locator.PersonRepository.GetById(dto.Id);

Version field is loaded by new value. but I need to set it from my PersonDTO object

person.Version = dto.Version

During update process NHibernate passes old value to sql and I don’t face with concurreny error.

What should I do to implement concurrency in this way.
Any help is appriciated.

Answer 1

As I understand your problem, I guess You have a field that its getter works fine but when you are trying to set it you face with problem, if it is so, then check the following considerations

• Check if your Version field that is not Readonly
• Check if it has a public setter not a private one
• Check if you have needed properties in your Mapper
• Check what is happening in your Person constructor that is not raise when you use GetByID method

provide more information if these ideas didn’t help you