How to write a Criteria Query when there's an <any> association

Question

I'm having some trouble constructing the correct Criteria to do a particular query - after an afternoon of consultation with Professor Google, I'm hoping that someone can point me in the right direction.

I have two entities of interest: OutputTsDef and NamedAttribute

What I'm trying to do is to find all OutputTsDef that have a particular NamedAttribute value.

I can write a detached Criteria to find all NamedAttributes that have a given name and value:

       var attributesCriteria
           = DetachedCriteria.For<INamedAttribute>()
               .Add(Expression.Eq("Name", "some name"))
               .Add(Expression.Eq("Value", "some value"));

How do I inject this in to a query for OutputTsDef to restrict the results?

       var criteria
           = nHibernateSession.CreateCriteria(typeof(IOutputTsDefEntity));
       // What do I write here?
       var results = criteria.List();

NamedAttribute looks like this - note the use of [Any] as we can have NamedAttributes on many kinds of entity.

[AttributeIdentifier("DbKey", Name = "Id.Column", Value = "NamedAttributeID")]
[Class(Table = "NamedAttributes")]
public class NamedAttribute : BusinessEntity, INamedAttribute
{
    [Any(0, Name = "Entity", MetaType = "System.String", IdType = "System.Int32")]
    [MetaValue(1, Class = "Sample.OutputTsDef, Sample.Entities", Value = "OTD")]
    [MetaValue(2, Class = "Sample.OutputTimeSeriesAttributesEntity, Sample.Entities", Value = "OTA")]
    [Column(3, Name = "OwnerType")]
    [Column(4, Name = "OwnerKey")]
    public virtual IBusinessEntity Entity { get; set; }

   [Property(Column = "Name")]
   public virtual string Name { get; set; }

   [Property(Column = "Value")]
   public virtual string Value { get; set; }

   ... omitted ...

}

In regular SQL, I'd just include an extra "where" clause like this:

where OutputTsDefId
      in ( select distinct OwnerKey
           from NamedAttributes
           where Name = ?
             and Value = ?
             and OwnerType = 'OTD' )

What am I missing?

(Question also posted to the NHUsers mailing list - I'll copy any useful information from there, here.)

Answer 1

Do the answers to this apparently similar hibernate question help?

Answer 2

This is what I ended up doing - embedding the SQL subquery check in this way:

const string subquery
    = "{alias}.OutputTsDefId in "
        +"( select OwnerKey "
        + " from NamedAttributes na "
        + " where na.Name = ? and na.Value = ? and OwnerType='OTD')";
criteria.Add(
    Expression.Sql(
        subquery,
        new object[] { attributeFilter.Name, attributeFilter.Value },
        new IType[] { NHibernateUtil.String, NHibernateUtil.String }));

This isn't ideal - I don't really like to tunnel past NHibernate in this way. But, it gets the job done, which counts for a lot.

I'm still interested in finding a pure NHibernate solution, if there is one.