I am getting an error in NHibernate.Collection.PersistentBag class when trying to load entities:
The value "MyProject.DomainModel.Operator" is not of type "MyProject.DomainModel.Operator" and cannot be used in this generic collection.
Notice that both value types are exactly the same. I've double-checked them in a comparer tool.
NHibernate is failing to add the value to a List collection at line bag.Add(element) .
The element variable is actually of type *object{DecoratorAopProxy_9cf850624c7e4ef9a8e2d9694bed26fd}*. I've noticed that the objects that can be successfully added to this list are of type object{MyProject.DomainModel.Operator}. This type is obtained from "quick watch" feature in VS2012 from the "Type" column.
Does anyone have an idea as to why NHibernate changes the type of this particular object to a proxy while others have pure entity types?
<class name ="PersonRole" table ="tblPersonRole" mutable ="false">
<id name="Id" column="PersonRoleID" type="Int32" access ="nosetter.lowercase-underscore">
<generator class="native"/>
</id>
<discriminator formula="case when RoleID in (2,4,5,6) THEN RoleID ELSE 0 END" />
<subclass discriminator-value="4" name="AccountManagerRole">
<bag name="Operators" >
<key column="OperatorID"></key>
<one-to-many class="BaseOperator"/>
<loader query-ref="LoadAllocatedOperators_ACCOUNTMANAGER"/>
</bag>
</subclass>
</class>
<class name="BaseOperator" table="tblOperator" lazy="true" >
<id name="Id" column="OperatorID" access ="nosetter.lowercase-underscore" type="Int32" unsaved-value="null">
<generator class="native" />
</id>
<discriminator column="OperatorType" type="string" />
<subclass discriminator-value ="OPR" name ="Operator" lazy="true">
<bag name="Customers" access="nosetter.camelcase-underscore" lazy="true" cascade="all-delete-orphan" inverse="true" fetch="join" >
<key column="OperatorId" />
<one-to-many class="MyProject.DomainModel.Customer, MyProject" not-found="ignore" />
</bag>
<subclass discriminator-value ="OPR2" name ="Operator2" lazy="true" />
</subclass>
</class>
So I do something like "select distinct accManager from AccountManagerRole accManager", which results in operators being loaded one at a time using their ID, and NHibernate crashes on one of them.
Related
Forgive me I am a newbie in NHibernate, I found some example in hbm.xml like below.
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="test" >
<class name="test.FieldSetMapping" table="fieldsetmapping" discriminator-value="2352" lazy="false">
<id name="Id" column="fieldsetmapping_id" type="Int64">
<generator class="test.NHibernate.IdGenerator, test">
<param name="table">nextinstanceid</param>
<param name="column">next</param>
<param name="max_lo">9</param>
</generator>
</id>
<discriminator column="mapping_type" type="Int32" />
<version name="LastUpdateNumber" column="last_update_number" type="Int32" unsaved-value="-1"/>
<property name="OwnerName" column= "owner_name" type="String"/>
<component name="FieldSetDefinitionId" class="test.ObjectId">
<property name="InstanceId" column= "fieldsetdefinition_id" type="Int64"/>
</component>
<property name="OwnerTypeClassId" column= "owner_type" />
<bag name="FieldMappings" cascade="all-delete-orphan" generic="true" lazy="false">
<key column="fieldsetmapping_id" not-null="true" />
<one-to-many class="test.FieldSet.FieldMapping, test" />
</bag>
<property name="MappingHandlerClass" column="handler_class" />
</class>
<subclass name="test.EntityFieldSetMapping, test" discriminator-value="2353" extends="test.FieldSetMapping, test" lazy="false" >
<property name="TargetEntityType" type="test.Internal.NHibernate.ClassIdType, test" not-null="false">
<column name="target_entity_type"/>
</property>
</subclass>
<class ...>
...
</class>
<class ...>
...
</class>
</hibernate-mapping>
But I don't know what does discriminator mean . I check the Nhibernate Doc 5.1.6.
The <discriminator> element is required for polymorphic persistence
using the table-per-class-hierarchy mapping strategy and declares a discriminator
column of the table. The discriminator column contains marker values that tell
the persistence layer what subclass to instantiate for a particular row.A restricted
set of types may be used: String, Char, Int32, Byte, Short, Boolean, YesNo, TrueFalse.
Does it mean if the mapping_type > 2352 the NH will initialize the subclass test.EntityFieldSetMapping for the row of the table fieldsetmapping? thanks.
NHibernate will use the discriminator to detect which class needs to instantiate on a polymorphic scenario.
If mapping_type = 2352, it will create an instance of test.FieldSetMapping
if mapping_type = 2353, it will create an instance of test.EntityFieldSetMapping
Any other value should generate an exception.
For following class mapping:
<class name="Person" table="Person" discriminator-value="null">
<id name="ID" column="ID" >
<generator class="identity"/>
</id>
<discriminator column="MasterId" />
<property name="LongName" column="LONGNAME" />
<property name="ShortName" column="SHORTNAME" />
// other stuff here ...
<subclass name="PersonHistory" discriminator-value="not null">
<property name="MasterId" />
</subclass>
</class>
when I execute:
var query =
from lac in session.Query<Person>()
orderby lac.LongName
select lac;
return query.ToList();
I get all entries from Person table, both with MasterId set to null and not null. Is there a way to get NHibernate fetch only entities with MasterId = null?
How about using discriminator formula in your case?
<discriminator formula="case when MasterId is null then 0 else 1 end" />
And then have discriminator attribute values set for classes:
For Person: discriminator-value="0"
For PersonHistory: discriminator-value="1"
In order to achieve what I wanted, I've created base class + two subclasses. This is the configuration:
subclasses with discriminator-value:
<subclass name="People" discriminator-value="null">
</subclass>
<subclass name="PeopleHistory" discriminator-value="not null">
<property name="MasterRowId" />
</subclass>
discriminator in base class:
<discriminator column="MasterRowId" />
I think the object model below is saying a Party and PartyName to have a many to one relatioship. An I think the cascade=all i the Party.hbm sshould be having NHib save the child PartyName(s).
But it clearly isn't...
Can someone explain why PartyName isn't being saved with Party and what to do to fix?
Cheers,
Berryl
MAPPING
<class name="Party" table="Parties">
<id name="Id">
<column name="PartyId" />
<generator class="hilo" />
</id>
<discriminator column="Type" not-null="true" type="string" />
<set access="field.camelcase-underscore" cascade="all" inverse="true" name="Names">
<key foreign-key="Party_PartyName_FK">
<column name="PartyNameId" />
</key>
<one-to-many class="Parties.Domain.Names.PartyName, Parties.Domain" />
</set>
<subclass
name="Smack.Core.TestingSupport.NHibernate.TestableDomain.SomeDopeyDomainModel.Student, Smack.Core.TestingSupport"
discriminator-value="Student"
>
<property name="Number" />
<many-to-one
class="Smack.Core.TestingSupport.NHibernate.TestableDomain.SomeDopeyDomainModel.Course, Smack.Core.TestingSupport"
foreign-key="Course_FK"
name="Course">
<column name="CourseId" index="CourseIndex" />
</many-to-one>
</subclass>
<many-to-one access="field.camelcase-underscore" class="Parties.Domain.Party" foreign-key="Party_FK" name="Party">
<column name="PartyId" index="PartyIndex" not-null="true"/>
</many-to-one>
<property name="TheRequiredName" not-null="true" length="50"/>
<property name="EverythingElse" />
<property name="ContextUsed" length="50"/>
<property name="Salutation" length="20"/>
<property name="EffectivePeriod" type="Smack.Core.Data.NHibernate.UserTypes.DateRangeUserType, Smack.Core.Data">
<column name="EffectiveStart"/>
<column name="EffectiveEnd"/>
</property>
Failing Test (and output)
[Test]
public void CanSaveAndLoad_AllProperties()
{
var partyName = NameSeeds.DevName;
partyName.Party = _party;
Assert.That(_party.Names.First(), Is.EqualTo(partyName));
using (var tx = _session.BeginTransaction())
{
_session.Save(_party);
tx.Commit();
}
_session.Clear();
Party foundParty;
using (var tx = _session.BeginTransaction())
{
foundParty = _session.Get<Party>(_party.Id); *** <=== name s/b saved!!
tx.Commit();
}
PartyName foundName = foundParty.Names.First();
//found.Look();
Assert.That(foundName, Is.EqualTo(partyName));
Assert.That(foundName.Party, Is.Not.Null);
Assert.That(foundName.TheRequiredName, Is.EqualTo(partyName.TheRequiredName));
Assert.That(foundName.EverythingElse, Is.EqualTo(partyName.EverythingElse));
Assert.That(foundName.ContextUsed, Is.EqualTo(partyName.ContextUsed));
Assert.That(foundName.Salutation, Is.EqualTo(partyName.Salutation));
Assert.That(foundName.EffectivePeriod, Is.EqualTo(partyName.EffectivePeriod));
}
NHibernate: INSERT INTO Parties (Type, PartyId) VALUES ('Parties.Domain.Party', #p0);#p0 = 32768 [Type: Int32 (0)]
NHibernate: SELECT party0_.PartyId as PartyId2_0_, party0_.Number as Number2_0_, party0_.CourseId as CourseId2_0_, party0_.Type as Type2_0_ FROM Parties party0_ WHERE party0_.PartyId=#p0;#p0 = 32768 [Type: Int32 (0)]
With the mapping of the Names <set> inverse=true, you will have to explicitly call session.Save(partyNameObject) on each member of the collection. If you are looking to have NHibernate automatically save the members of the set when the PartyObject is saved, you need to change the Names <set> inverse attribute to inverse=false. This tells Nhibernate that you want Party to control the relationship between Party and PartyName. You must also remember to add each partyNameObject to the Party.Names collection. Otherwise, they won't be saved when you call Session.Save(partyObject). Keep in mind that having the parent control the relationship may be handy, but if you happen to save the PartyObject without having Loaded the PartyNames collection, NHibernate will update their Party FK to Null. In this scenario with certain Cascade options set on the Names <set>, you might find Nhibernate Deleting them as well.
I am working on a legacy database which is quite intricate.
The table customers is shared with the suppliers and who created this structure used a flag to identify the customers.
Since I am only interested in working with records defined as customers I've added a where clause to my mapping:
<?xml version="1.0" encoding="utf-8"?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MyAssembly" namespace="MyAssembly.Domain">
<class name="Customer" table="ANSADID" mutable="false" where="ANFCLI = 'Y'">
<composite-id>
<key-property name="CustomerCode" column="ANCOCO" type="String" length="10"></key-property>
<key-property name="Company" column="ANCOSO" type ="String" length="5"></key-property>
</composite-id>
<property name="Name" column="ANINCO" type="String" length="100"></property>
</class>
</hibernate-mapping>
As you can see I've pre-filtered all my customers with this clause: ANFCLI = 'Y'
Everything works perfectly fine if I query customers (the where clause is used):
var customers = session.QueryOver<Domain.Customer>()
.Where(t => t.Company == "ABC01")
.List();
But if I query the orders table - where I've got a many-to-one association:
<?xml version="1.0" encoding="utf-8"?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="MyAssembly" namespace="MyAssembly.Domain">
<class name="Order" table="OCSAORH" mutable="false" where="OCHAMND = 0">
<composite-id>
<key-property name="Number" column="OCHORDN" type="String" length="10"></key-property>
<key-property name="Ver" column="OCHAMND" type="Int32"></key-property>
<key-property name="Company" column="OCHCOSC" type="String" length="5"></key-property>
</composite-id>
<many-to-one name="Customer" class="Customer" lazy="proxy" fetch="join">
<column name="OCHCLII" not-null="true"/>
<column name="OCHCOSC" not-null="true"/>
</many-to-one>
</class>
</hibernate-mapping>
the filter on the entity customers is lost.
I was reading somewhere that the where clause doesn't work on a association and you have to use a where clause on the collection (bag, set, etc etc) but, how can I do that with a many-to-one?
Thanks for you help.
What about mapping Customer using a discriminator using ANFCLI and then setting the discriminator value to 'Y'. I think NHibernate will treat this a little more rigourously than a where clause.
<class name="Customer" table="ANSADID" mutable="false" discriminator-value="Y">
<composite-id>
<key-property name="CustomerCode" column="ANCOCO" type="String" length="10" />
<key-property name="Company" column="ANCOSO" type ="String" length="5" />
</composite-id>
<discriminator column="ANFCLI" />
<property name="Name" column="ANINCO" type="String" length="100" />
</class>
I think degorolls is right:
You would need to have a super class called "Person", and two sub types called "Customer" and "Supplier".
Then you set your mapping so it uses the ANFCLI field as a discriminator, with the Y value for Customer and the N value for Supplier.
This way, you'll have a nice and transparent polymorphism.
(you'll be able to do stuff like "from Customer", or "from Supplier", and that will automagicaly add the where clause).
Hope that helps!
I'm also a newbie using NHibernate but perhaps you can map that relation (Order to Customer) using a bag (as if it would be one to many)!
Consider the following Hibernate mapping file:
<hibernate-mapping ...>
<class name="ContentPackage" table="contentPackages">
<id name="Id" column="id" type="int"><generator class="native" /></id>
...
<bag name="Clips" table="contentAudVidLinks">
<key column="fk_contentPackageId"></key>
<many-to-many class="Clip" column="fk_AudVidId"></many-to-many>
<filter name="effectiveDate" condition=":asOfDate BETWEEN startDate and endDate" />
</bag>
</class>
</hibernate-mapping>
When I run the following command:
_session.EnableFilter("effectiveDate").SetParameter("asOfDate", DateTime.Today);
IList<ContentPackage> items = _session.CreateCriteria(typeof(ContentPackage))
.Add(Restrictions.Eq("Id", id))
.List<ContentPackage>();
The resulting SQL has the WHERE clause on the intermediate mapping table (contentAudVidLinks), rather than the "Clips" table even though I have added the filter attribute to the Bag of Clips.
What am I doing wrong?
Figured it out. For anyone interested, I had my <filter> attribute in the wrong place:
Before:
<bag name="Clips" table="ctv_bb_contentAudVidLinks">
<key column="fk_contentPackageId"></key>
<many-to-many class="Clip" column="fk_AudVidId"></many-to-many>
<filter name="effectiveDate" condition=":asOfDate BETWEEN startDate and endDate" />
</bag>
After:
<bag name="Clips" table="ctv_bb_contentAudVidLinks">
<key column="fk_contentPackageId"></key>
<many-to-many class="Clip" column="fk_AudVidId">
<filter name="effectiveDate" condition=":asOfDate BETWEEN startDate and endDate" />
</many-to-many>
</bag>