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Problem using nHibernate 2.0 Session.Get <T> for a class with a composite identifier

I am having problems with something that (I think) should be simple but cannot find any clear information.

In a scenario where I have three tables describing a domain in which a person can have several tasks:

Person - has PersonId, Name
Job - has JobId, JobName
PersonJob - has PersonId, JobId, YearsOfEmployment

Note. In my object model, I have entities representing each table. I have this third object to represent the Person / Job relationship, because it has useful metadata (YearsOfEmployment) and not just a simple join table.

So, if I knew PersonId and JobId, is there an easy way to use a session and return an object corresponding to these identifiers?

Or, in another way, because I already know that primary keys are a dead brain, an easy way I can turn SQL "SELECT YearsOfEmployment FROM PersonJob WHERE PersonId = 1 AND JobId = 1" into something like:

var keys = new {PersonId=1, JobId=2};
PersonJob obj = Session.Get<PersonJob>(keys);

By the way: the cards would look something like this:

<class name="Person" table="dbo.Person" lazy="true">
  <id name="PersonId">
    <generator class="native"/>
  </id>
  <property name="Name"/>
</class>
<class name="Job" table="dbo.Job" lazy="true">
  <id name="JobId">
    <generator class="native"/>
  </id>
  <property name="JobName"/>
</class>
<class name="PersonJob" table="dbo.PersonJob" lazy="true">
  <composite-id>
    <key-property name="PersonId"></key-property>
    <key-property name="JobId"></key-property>
  </composite-id>
  <property name="YearsOfEmployment"/>
</class>
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2 answers

Ok, I answered my question. I think posting your problem is almost as painful as talking to someone. If I were to create a composite PersonJob identifier for a component or class, i.e.

<class name="PersonJob" table="dbo.PersonJob" lazy="true">
    <composite-id name="PersonJobKey" class="PersonJobKey">
      <key-property name="PersonId"></key-property>
      <key-property name="JobId"></key-property>
    </composite-id>
</class>

Then I can just do this:

PersonJobKey key = new PersonJobKey() { PersonId = 1, JobId = 1 };  
PersonJob obj = Session.Get<PersonJob>(key);  
int yearsOfEmployment = obj.YearsOfEmployment;

cool. hope this helps someone else figure it out ...

+8

, , , . , . - :

Session.Get<SalesRepArea>(new { AreaCode = "ACode", RegionCode = "RCode"});

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<class name="SalesRepArea">
   <composite-id>
      <key-property 
         name="AreaCode" column="AreaCode" type="String" length="12" />
      <key-property 
         name="RegionCode" column="RegionCode" type="String" length="12" />
   </composite-id>

, ,

SalesRepArea myArea = Session.Get<SalesRepArea>(
   new SalesRepArea()
   { 
      AreaCode = "ACode", 
      RegionCode = "RCode" 
   }
);

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+3

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