session.Query<T> is new in 3.x, using the integrated Linq provider, which is HQL-based instead of Criteria-based behind the scenes, allowing for more flexibility.
Diego On Thu, Jun 24, 2010 at 12:13, ben <[email protected]> wrote: > Fabio, > > Is session.Query<T> new? > > Using what you have with session.Linq<T>: > > var query = from v in _session.Linq<Vehicle>() > where v.Carrier == > _session.Load<Carrier>(carrierId) > select v; > > Generates the same sql as what I have in the my original Linq example: > > NHibernate: SELECT this_.Id as Id1_1_, this_.VehicleType as > VehicleT2_1_1_, this_.BusinessRef as Business3_1_1_, this_.CarrierId > as CarrierId1_1_, carrier1_.Id as Id2_0_, carrier1_.Name as Name2_0_, > carrier1_.BusinessRef as Business3_2_0_, carrier1_.Enabled as > Enabled2_0_ FROM Vehicles this_ left outer join Carriers carrier1_ on > this_.CarrierId=carrier1_.Id WHERE this_.CarrierId = @p0;@p0 = 1 > > Thanks > Ben > > On Jun 23, 12:38 pm, Fabio Maulo <[email protected]> wrote: > > from v in session.Query<Vehicle>() where v.Carrier == > > session.Load<Carrier>(1) select v > > > > > > > > On Wed, Jun 23, 2010 at 8:16 AM, ben <[email protected]> wrote: > > > I've got a one to many association between a Carrier and Vehicle. In > > > my database my Vehicle table has a foreign key CarrierId. > > > > > The most efficient way to query vehicles by carrier would be: > > > > > select ... from Vehicles where Vehicles.CarrierId == 1 > > > > > However, if I use QBC: > > > > > var fromDb = session.CreateCriteria<Vehicle>() > > > .CreateCriteria("Carrier", > > > global::NHibernate.SqlCommand.JoinType.InnerJoin) > > > .Add(Expression.Eq("Id", 1)) > > > .AddOrder(new Order("BusinessRef", true)) > > > .List<Vehicle>(); > > > > > The result is: > > > > > NHibernate: SELECT this_.Id as Id1_1_, this_.VehicleType as > > > VehicleT2_1_1_, this_.BusinessRef as Business3_1_1_, this_.CarrierId > > > as CarrierId1_1_, carrier1_.Id as Id2_0_, carrier1_.Name as Name2_0_, > > > carrier1_.BusinessRef as Business3_2_0_ FROM Vehicles this_ inner join > > > Carriers carrier1_ on this_.CarrierId=carrier1_.Id WHERE carrier1_.Id > > > = @p0 ORDER BY carrier1_.BusinessRef asc;@p0 = 1 > > > > > If I use NHibernate.Linq: > > > > > var fromDb2 = session.Linq<Vehicle>() > > > .Where(x => x.Carrier.Id == 1) > > > .OrderBy(x => x.BusinessRef) > > > .ToList(); > > > > > The result is similar but always seems to do an outer join (how can I > > > force it to be left inner?): > > > > > NHibernate: SELECT this_.Id as Id1_1_, this_.VehicleType as > > > VehicleT2_1_1_, this_.BusinessRef as Business3_1_1_, this_.CarrierId > > > as CarrierId1_1_, carrier1_.Id as Id2_0_, carrier1_.Name as Name2_0_, > > > carrier1_.BusinessRef as Business3_2_0_ FROM Vehicles this_ left outer > > > join Carriers carrier1_ on this_.CarrierId=carrier1_.Id WHERE > > > carrier1_.Id = @p0 ORDER BY this_.BusinessRef asc;@p0 = 1 > > > > > Finally if I use HQL (as much as I dislike using "magic" strings), the > > > result is exactly what I would expect and seems the most efficient: > > > > > var fromDb3 = session.CreateQuery("from Vehicle where > > > Carrier.Id = :id") > > > .SetParameter("id", 1) > > > .List<Vehicle>(); > > > > > NHibernate: select vehicle0_.Id as Id1_, vehicle0_.VehicleType as > > > VehicleT2_1_, vehicle0_.BusinessRef as Business3_1_, > > > vehicle0_.CarrierId as CarrierId1_ from Vehicles vehicle0_ where > > > vehicle0_.carrier...@p0;@p0 = 1 > > > > > So why do I get this difference and more importantly, how can I use > > > QBC or Linq to generate the same SQL as HQL does? > > > > > Thanks, > > > Ben > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "nhusers" group. > > > To post to this group, send email to [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]<nhusers%[email protected]> > <nhusers%[email protected]<nhusers%[email protected]> > > > > > . > > > For more options, visit this group at > > >http://groups.google.com/group/nhusers?hl=en. > > > > -- > > Fabio Maulo > > -- > You received this message because you are subscribed to the Google Groups > "nhusers" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]<nhusers%[email protected]> > . > For more options, visit this group at > http://groups.google.com/group/nhusers?hl=en. > > -- You received this message because you are subscribed to the Google Groups "nhusers" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.
