Question

I have an entity Customer

public class Customer {     public virtual int ID { get; set; }     public virtual string Firstname { get; set; }     public virtual string Lastname { get; set; } } 

and my DAL method is :

    public IList<Customer> GetCustomers(Customer example)     {         var customers = default(IList<Customer>);          using (var sessiong = GetSession())         {             customers = sessiong.CreateCriteria(typeof(Customer))                 .Add(Example.Create(example))                 .List<Customer>();         }          return customers;     } 

but the problem is that when I call my method like this

    var exemple = new Customer() { ID = 2 };     var customers = provider.GetCustomers(exemple); 

I have a collection of all my customers in the database because NHibernate generates the following SQL query

NHibernate: SELECT this_.CustomerId as CustomerId0_0_, this_.Firstname as Firstname0_0_, this_.Lastname as Lastname0_0_ FROM Customers this_ WHERE (1=1) 

NHibernate supports QBE on primary key ? What am I doing wrong ?

P.S. I’ve forgotten to mention the version of NHibernate that I’m using. It’s 2.0.1.GA.

Answer 1

‘The ID is ignored when using query by example. This is done because an example object with the id set would return only one object anyways.’ – http://forum.hibernate.org/viewtopic.php?t=927063 and http://forum.hibernate.org/viewtopic.php?p=2351666&sid=c22d2c37f8d67e268b6ffe547f57ad9e
This is for Hibernate. NHibernate was ported from it. So I’m sure that this is by design in NHibernate too. So use Get instead of QBE on id.