I'm using by code mappings and trying to map a manytomany. This works fine but I need OrderBy for the child collection items. I noticed this has been omitted (it does exist in the HBM mappings). e.g.
public class Mapping : EntityMapper<Category>
{
public Mapping()
{
Set(x => x.Items, m =>
{
m.Table("ItemCategories");
m.Key(k => k.Column("CategoryId"));
m.Inverse(true);
m.Cascade(Cascade.None);
}, col => col.ManyToMany(m =>
{
m.Columns(x => x.Name("ItemId"));
//m.OrderBy("Score desc"); // missing in Nh4.x?
}));
}
}
Is there a workaround for this? I tried following the suggestion in this article whereby I can set the property before the session factory is built but it has no effect. e.g.
cfg.GetCollectionMapping(typeof(Category).FullName + ".Items").ManyToManyOrdering = "Score desc";
cfg.BuildSessionFactory();
Am I doing something wrong or is OrderBy on manytomany not supported in Nh4?
Also, is it possible to restrict the maximum number of items retrieved in the collection?
Replaced the many to many with one to many and introduced an entity that represents the relationship (followed advice from this article).
This has the upside of allowing you to map the order-by column as well as other columns, and also solved the issue of restricting the number of items in the collection by using the one-to-many's Where() and Filter() clauses.
Related
Simplified Model:
public class GolfCourseDetailsPart : ContentPart<GolfCourseDetailsRecord>
{
public bool ShowInHomePage {... //Get and Set using Retrieve and Store methods
}
Simplified Migrations:
ContentDefinitionManager.AlterTypeDefinition("GolfCourse", gc => gc
//...
.WithPart(typeof(GolfCourseDetailsPart).Name)
);
I need to filter all items of type "GolfCourse" to get only the ones that have ShowInHomePage set to true.
Filter:
I have created a filter implementing the IFilterProvider interface and it returns all the GolfCourse content items but I couldn't get to filter by ShowInHomePage yet:
private void ApplyFilter(FilterContext context)
{
context.Query = context.Query.Join(x=>x.ContentPartRecord(typeof(GolfCourseDetailsRecord)));
}
How could I get to filter by the property ShowInHomePage??
You are almost there, the only part missing is the .Where clause. In a HQL query it looks like this:
private void ApplyFilter(FilterContext context)
{
context.Query = context
.Query
.Join(x => x.ContentPartRecord(typeof(GolfCourseDetailsRecord)))
.Where(x => x.ContentPartRecord<GolfCourseDetailsRecord>(), g => g.Eq("ShowInHomePage", true));
}
Is there any reason you want to create an IFilterProvider?
Those will be only useful if you want to have a customized filter available for query projections.
If you simply want to get filtered data programmatically then I would use Query method of ContentManager.
Here is a set of samples on how querying Orchard, I think it will be more useful for you than if I simply put here the query you need: https://orchardtrainingdemo.codeplex.com/SourceControl/latest#Controllers/ContentsAdminController.cs
Using nHib 3.2, I'm interested in caching all my entity's properties, except for a formula property which I would like to be calculated with each Get.
Is this possible?
here's my mapping:
public TransactionNHibernateMapping()
{
Table("TransactionInfo");
Id(transaction => transaction.TransactionId, m => m.Generator(Generators.GuidComb));
Cache(c =>
{
c.Include(CacheInclude.All);
c.Usage(CacheUsage.ReadWrite);
});
Property(transaction => transaction.HighestSeverity, m => m.Formula("(Select max(LogEntryInfo.Severity) from LogEntryInfo where LogEntryInfo.TransactionId = TransactionId)"));
}
now, although 2nd level cache is enabled, this entity is always re-loaded from the database.
If I remove the HighestSeverity property mapping, caching works as expected.
I've tried playing with the Generated option of the formula field, but that didn't seem to help.
any other ideas?
This NHibernate blog entry notes how detached QueryOver queries (analogous to DetachedCriteria) can be created (using QueryOver.Of<T>()). However, looking this over, it doesn't look analogous to me at all.
With DetachedCriteria, I would create my instance and set it up however I need, and afterwards call GetExecutableCriteria() to then assign the session and execute the query. With the "detached" QueryOver, most of the API is unavailable (ie, to add restrictions, joins, ordering, etc...) until I call GetExecutableQueryOver, which requires takes an ISession or IStatelessSession, at which point you are no longer disconnected.
How do you work with detached QueryOver instances?
EDIT:
Actual problem was related to how I'm storing the detached QueryOver instance:
public class CriteriaQuery<T>
{
internal protected QueryOver<T> _QueryOver { get; set; }
public CriteriaQuery()
{
_QueryOver = QueryOver.Of<T>();
}
// Snip
}
It should be a QueryOver<T, T>.
I'm using NHibernate 3.1.0.4000. The following code compiles successfully:
Employee salesRepAlias = null;
var query = QueryOver.Of<Customer>()
.JoinAlias(x => x.SalesRep, () => salesRepAlias)
.Where(x => x.LastName == "Smith")
.Where(() => salesRepAlias.Office.Id == 23)
.OrderBy(x => x.LastName).Asc
.ThenBy(x => x.FirstName).Asc;
return query.GetExecutableQueryOver(session)
.List();
This illustrates using restrictions, joins, and ordering on a detached QueryOver just like you would with a regular one.
Could you please post the code that demonstrates the API features that are unavailable?
Here's my (simplified) model: Ticket -> Customer Callback (s)
I have my Ticket mapped so that when it's loaded, the Callbacks are as well.
base.HasMany<TechSupportCallback>(x => x.Callbacks)
.KeyColumn(Fields.TRACKED_ITEM_ID)
.Not.LazyLoad()
.Inverse()
.Cache.ReadWrite();
This is not lazy loading because otherwise I'll get 'no session to load entities' when the web service tries to serialize (and load) the proxy. (Using repositories to fetch data.)
It's also bi-directional .. (in the CallbackMap)
base.References(x => x.Ticket)
.Column(Fields.TRACKED_ITEM_ID)
.Not.Nullable();
Now .. we need to show an agent a list of their callbacks - JUST their callbacks.
-- When I query using Criteria for the Callbacks, I cannot prevent the Ticket (and subsequently it's entire graph, including other collections) from being loaded. I had previously tried to set FetchMode.Lazy, then iterate each resulting Callback and set Ticket to null, but that seems to be ignored.
// open session & transaction in using (..)
var query = session.CreateCriteria<TechSupportCallback>()
.SetCacheable(true)
.SetCacheRegion("CallbacksByUserAndGroups")
.SetFetchMode("Ticket", FetchMode.Lazy) // <-- but this doesn't work!
.SetMaxResults(AegisDataContext.Current.GetMaxRecordCount())
;
rValue = query.List<TechSupportCallback>();
rvalue.ForEach(x => x.Ticket = null;); // <-- since this is already retrieved, doing this merely prevents it from going back across the wire
tx.Commit();
// usings end (..)
Should I be doing this with a projection instead?
The problem with that .. is I've not been able to find an example of projections being used to populate an entity, or a list of them -- only to be used as a subquery on a child entity or something similar to restrict a list of parent entities.
I could really use some guidance on this.
[EDIT]
I tried using a projection as suggested but:
I'm getting the following: (this was because of a bug, and so I've since stopped using the cache and it works. http://nhibernate.jira.com/browse/NH-1090)
System.InvalidCastException occurred
Message=Unable to cast object of type 'AEGISweb.Data.Entities.TechSupportCallback' to type 'System.Object[]'.
Source=NHibernate
StackTrace:
at NHibernate.Cache.StandardQueryCache.Put(QueryKey key, ICacheAssembler[] returnTypes, IList result, Boolean isNaturalKeyLookup, ISessionImplementor session)
InnerException:
at
rValue = query.List<TechSupportCallback>();
with the projection list defined like
// only return the properties we want!
.SetProjection(Projections.ProjectionList()
.Add(Projections.Alias(Projections.Id(), ex.NameOf(x => x.ID))) //
.Add(Projections.Alias(Projections.Property(ex.NameOf(x => x.ContactID)), ex.NameOf(x => x.ContactID)))
// ...
)
.SetResultTra...;
rValue = query.List<TechSupportCallback>();
mapped like
public TechSupportCallbackMap()
{
base.Cache.ReadWrite();
base.Not.LazyLoad();
base.Table("TS_CALLBACKS");
base.Id(x => x.ID, Fields.ID)
.GeneratedBy.Sequence("SEQ_TS_CALLBACKS");
base.References(x => x.Ticket)
.Column(Fields.TRACKED_ITEM_ID)
.Not.Nullable();
base.Map(x => x.TrackedItemID, Fields.TRACKED_ITEM_ID)
.Not.Insert()
.Not.Update()
.Generated.Always()
;
// ...
}
This sounds like it's a job exactly for projections.
var query = session.CreateCriteria<TechSupportCallback>()
.SetCacheable(true)
.SetCacheRegion("CallbacksByUserAndGroups")
.SetFetchMode("Ticket", FetchMode.Lazy)
.SetMaxResults(AegisDataContext.Current.GetMaxRecordCount())
.SetProjection(Projections.ProjectionList().
.Add(Projections.Alias(Projections.Id(), "Id")
.Add(Projections.Alias(Projections.Property("Prop"), "Prop")))
.SetResultTransformer(Transformers.AliasToBean<TechSupportCallback>())
;
Simply list all the properties you want to include and exclude the Ticket entity. You can even create a POCO class simply for encapsulating the results of this query. Rather than using an existing entity class.
First time rocking it with NHibernate/Fluent so apologies in advance if this is a naive question. I have a set of Models I want to map. When I create my session factory I'm trying to do all mappings at once. I am not using auto-mapping (though I may if what I am trying to do ends up being more painful than it ought to be). The problem I am running into is that it seems only the top map is taking. Given the code snippet below and running a unit test that attempts to save 'bar', it fails and checking the logs I see NHibernate is trying to save a bar entity to the foo table. While I suspect it's my mappings it could be something else that I am simply overlooking.
Code that creates the session factory (note I've also tried separate calls into .Mappings):
Fluently.Configure().Database(MsSqlConfiguration.MsSql2008
.ConnectionString(c => c
.Server(#"localhost\SQLEXPRESS")
.Database("foo")
.Username("foo")
.Password("foo")))
.Mappings(m =>
{
m.FluentMappings.AddFromAssemblyOf<FooMap>()
.Conventions.Add(FluentNHibernate.Conventions.Helpers
.Table.Is(x => "foos"));
m.FluentMappings.AddFromAssemblyOf<BarMap>()
.Conventions.Add(FluentNHibernate.Conventions.Helpers
.Table.Is(x => "bars"));
})
.BuildSessionFactory();
Unit test snippet:
using (var session = Data.SessionHelper.SessionFactory.OpenSession()) {
var bar = new Bar();
session.Save(bar);
Assert.NotNull(bar.Id);
}
You're doing it wrong. :)
Firstly, m.FluentMappings.AddFromAssemblyOf<FooMap>() and m.FluentMappings.AddFromAssemblyOf<BarMap>() are doing exactly the same thing (if FooMap and BarMap are in the same assembly). Each one just tells Fluent NHibernate to scan the assembly that contains the generic type; so if both types are in the same assembly, it'll scan it twice.
Secondly, the Conventions call is not scoped to the specific assembly you call it after, it's for the whole set of mappings. So what you're doing is supplying two conventions to set the table name to an explicit value, and the second one is the last one to be applied. What you want to do is use the x parameter (which is the entity type) and create your table name from that.
What you need is something like this:
.Mappings(m =>
{
m.FluentMappings.AddFromAssemblyOf<FooMap>()
.Conventions.Add(Table.Is(x => x.Name + "s"));
})
Obviously my implementation is naive, and depending on what your table naming convention is you might want to use a pluraliser (I believe Castle has one, but it shouldn't be hard to find one with google).
You can read up more about conventions on the Fluent NHibernate wiki.
With classmap you specify the table name in the mapping. If not specified, it will be the same as the entity class name.
class FooMap : ClassMap<Foo>
{
public FooMap()
{
Table("foos");
}
}
Conventions apply to all mappings. As you added 2 table name conventions, only 1 will take effect.
Are your FooMap and BarMap in the same assembly? You only need to add each assembly once.
.Mappings(m => m.FluentMappings.AddFromAssemblyOf<FooMap>())
Just want to share this will automatically add plural name either s, es, ies based on the end alphabet. Not so sure about grammar and some exception but this seems ok for me. Any exception use Table("foos") like #Lachlan Roche said. E.g. Customer class will have Customers table and Category class will have Categories table.
Modified #James Gregory answer:
.Mappings(m =>
{
m.FluentMappings.AddFromAssemblyOf<FooMap>()
.Conventions.Add(Table.Is(x => GetPluralName(x.Name));
})
public static string GetPluralName(string oldName)
{
// This is the very simple. Just ignore exception like days, boys, photos and other specific nouns.
if (oldName.EndsWith("y"))
return oldName.Remove(oldName.Length - 1) + "ies";
else if (oldName.EndsWith("s") || oldName.EndsWith("e") || oldName.EndsWith("h") || oldName.EndsWith("z") || oldName.EndsWith("o")) // Sibilant consonant or "o"
return oldName + "es";
return oldName + "s";
}