Question

I’m trying to code the following HQL query using the Criteria API:

var userList = _session                 .CreateQuery('select u from User u where u.Role.ID=3 and u.Customer.ID=:cID')                 .SetInt32('cID', 1)                 .List<User>(); 

(3 NHibernate objects : User(ID, Name, Role, Customer), Role(ID, Name) and Customer(ID, Name).

I tried the following but it doesn’t work because NHibernate tries to find a Customer associated with a Role:

var userList = _session             .CreateCriteria(typeof(User))             .CreateCriteria('Role')             .Add(Restrictions.Eq('ID', 3) )             .CreateCriteria('Customer')             .Add(Restrictions.Eq('ID', 1) )             .List<User>(); 

Any other way (that works!) of doing it?

Answer 1

You can use alias

var userList = _session         .CreateCriteria(typeof(User), 'u')         .CreateAlias('u.Role', 'r')         .Add(Restrictions.Eq('r.ID', 3) )         .CreateAlias('u.Customer', 'c')         .Add(Restrictions.Eq('c.ID', 1) )         .List<User>(); 

Hope it helps