I've got a collection that I want to have sorted by a field of another table to which it is related (which maps as a property of another object, incidentally).

I've been trying to work out how this can be done, but the <map> collection mapping allows for <index>, which sorts on a column in the table the collection refers to, or <index-many-to-many> which seems to be for sorting by types (?!) which I can't figure out.

In essence, what I'm trying to do is something like the following:



...where from the above the index column is found in the Modules table, not the ModuleParameterSets table.

Can something like this be done? I've seen references to foreign-key attributes in the mapping schema, but I can't figure out how to do this.

Help?

Symon.

You should rethink your requirements: map is in fact a hashtable which can not be considered as a sorted collection. And index of the map is used for a key in this hashtable.

Ok, fair enough, however I'm not stuck on map.

My essential requirement is a collection that can be reorganized based on values from a collection mapped to another table. I don't want to replicate the ordering values between the two tables as they could potentially become out of synch.

Symon.

I don't exactly realize your database structure and classes mapping, but maybe mapping of the collection to a view will help? In this view you can combine association table with sort field. You will need triggers for update and insert records in the view, though (INSTEAD OF, to be correct).

Ah, fantastic idea! *slaps forehead*

Fortunately the collection I'm talking about will be read only, so there's no need to deal with updates.

Thanks xor!

Cheers,

Symon.