Row versioning in NHibernate

Question

I'm developing a social app, which will provide users to create walls for messages (like on FB) and invite their friends. I have a table in my DB that contains the walls and their version (in TimeStamp), meaning - their last update time.

When someone updates a wall, the version will be updated and I want the user to receive this version. I'm using NHibernate and defined my version row to be type of Version, but I couldn't find a way to update a row AND receiving the new version in one atomic action, to prevent concurrency problems.

Is there a way to do this? Is there a better way to solve this problem?

Answer 1

the base entity,

public abstract class AuditBase
{       
    private int? _rowVersion = 0;

    public virtual int? RowVersion
    {
        get { return _rowVersion; }
        set { _rowVersion = value; }
    }
}

the entity,

    public partial class AXSERVICES : AuditBase
{}

you can try DefaultUpdateEventListener and DefaultSaveEventListener

for example

    public class CustomSaveEventListener : DefaultSaveEventListener
{

    protected override object PerformSave(object entity, object id, IEntityPersister persister, bool useIdentityColumn, object anything, IEventSource source, bool requiresImmediateIdAccess)
    {
        ((AuditBase)entity).RowVersion = 0;
        object obj = base.PerformSave(entity, id, persister, useIdentityColumn, anything, source, requiresImmediateIdAccess); 

return obj;
        }
    }