Delete rows that not in subquery - ends with NHibernate.QueryException:
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I would like to delete all rows from table A that are not exist in table B.
In order to do it I use session.Delete(query) as follows:

    Session.Delete<A>("FROM A WHERE id NOT IN (SELECT vpg_id FROM B)");

I get the following error:

    NHibernate.QueryException: could not resolve property: vpg_id of: A [FROM A WHERE Id NOT IN (SELECT vpgid FROM B)]

I tried also doing it using HQL as follows:

    Session.CreateQuery("DELETE A WHERE id NOT IN (SELECT vpg_id FROM B)").ExecuteUpdate();
and get this Exception:

        NHibernate.QueryException: No data type for node: IdentNode vpg_id [DELETE A WHERE id NOT IN (SELECT vpg_id FROM B)]