public IQueryable<T> Query(Expression<Func<T, bool>> predicate)
{
    IQueryable<T> returnValue;
    using (ITransaction transaction = _session.BeginTransaction())
    {
        try
        {
            returnValue = _session.Linq<T>().Where(predicate);
            transaction.Commit();
        }
        catch (Exception ex)
        {
            transaction.Rollback();
            Log.Error(this,ex.Message,ex);
            throw;
        }
    }
    return returnValue;
}