Cannot use order-by with generic set

stovesy · **Joined:** Tue Jun 06, 2006 4:47 am **Posts:** 25

I'm using NHibernate-1.2.0.Alpha1-debug with .Net 2.0
I can see why this error is happening, but I dont know how to get round it,

My Mapping file contains

Code:

      <!-- A list of items belonging to this invoice header -->
      <set name="items" table="tblinvoiceitems" order-by="itemnumber">
         <key column="headerptr"/>
         <one-to-many class="invoiceItem"/>
      </set>

And my Invoiceheader class contains.

Code:

private ICollection<invoiceItem> _items;
public virtual ICollection<invoiceItem> items
{
   get {
      return _items;
   }
   set { _items = value; }
}

So my question is, how do I get sorted sets to work with .NET 2 & NHibernate-1.2.0.Alpha1-debug ?
Can I use .Net 2.0 collections ?
Do I have to use iesi ?

Many thanks

avissar · **Posted:** Wed Apr 11, 2007 9:53 am

It was also asked in the JIRA (http://jira.nhibernate.org/browse/NH-939)

Sergey Koshcheyev said:

Quote:

order-by is used for collections that maintain order, and there is no such collection implementing ISet<T>. If you don't need to maintain the order, then you don't need order-by.

But in that case, there is a problem for using a collection that don't persist the order (no index column in db), but do want to retrieve the elements in a specific order.

And suggestions?

Cheers,
Tomer.