How to map a property with formula in NHibernate?

问题

I have a class which I want to add a property with using formula attribute.

Here is the mapping that I use in mapping file.

<property name="CurrentUserVote" type="Climate.Domain.Vote, Climate.Domain" formula="(select v from Vote v where v.AchievementId=Id and (v.IP=:CurrentUserVoteFilter.CurrentUserIP))"></property>

As you see, I want this property to be an object which refers to class that already has an nhibernate mapping. But this mapping gives a mapping exception;

Could not determine type for: Climate.Domain.Vote, Climate.Domain, for columns: NHibernate.Mapping.Formula( (select v from Vote v where v.AchievementId=Id and (v.IP=:CurrentUserVoteFilter.CurrentUserIP)) )

Is it possible to map a property with formula attribute to a class?

Thanks in advance.

回答1:

The property type must be a IUserType. See

• NHibernate property mapping: columns and formula
• http://blog.khedan.com/2009/01/eager-loading-from-formula-in.html

来源：https://stackoverflow.com/questions/2403915/how-to-map-a-property-with-formula-in-nhibernate