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nhibernatenhibernate-criteria

NHibernate Criteria Restriction vs Expression

If I search for NHibernate Criteria API query examples in internet there are examples that use Restrictions and others use Expression. What are the differences between those two?

For example:

posts = session.CreateCriteria<Post>()
    .Add(Expression.Eq("Id", 1))
    .List<Post>();

posts = session.CreateCriteria<Post>()
    .Add(Restrictions.Eq("Id", 1))
    .List<Post>();
Solution

  • I think Restrictions were released in NH2 and is now the favoured way.

    According to Resharper whenever I use Expression I get a hint to say Access to a static member of a type via a derived type

    Also according to this post by Ayende:-

    Prefer to use the Restrictions instead of the Expression class for defining Criteria queries.