[2.2] exception raised on BuildSessionFactory

graphicsxp · **Joined:** Thu Aug 14, 2008 5:31 pm **Posts:** 20

Hello,

I've got the following exception when I do :

Code:

ISessionFactory sessionFactory = (new Configuration()).Configure().BuildSessionFactory();

DataTransfer.Mappings.RssFeedCountries.hbm.xml(4,6): XML validation error: The element 'class' in namespace 'urn:nhibernate-mapping-2.2' has invalid child element 'property' in namespace 'urn:nhibernate-mapping-2.2'. List of possible elements expected: 'urn:nhibernate-mapping-2.2:meta urn:nhibernate-mapping-2.2:jcs-cache urn:nhibernate-mapping-2.2:cache urn:nhibernate-mapping-2.2:id urn:nhibernate-mapping-2.2:composite-id'.

I don't understand what the problem is. My mapping file for this table looks like this :

<?xml version="1.0" encoding="utf-8"?>

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">

<class name="DataTransfer.RssFeedCountries,DataTransfer" table="RSSFeedCountries" lazy="true">

<property type="int" not-null="true" name="RssFeedCountryid" column="[RSSFeedCountryID]" />

<property type="string" not-null="true" length="50" name="RssFeedCountry" column="[RSSFeedCountry]" />

</class>

</hibernate-mapping>

Does someone know what I'm doing wrong ?

Thanks

wolli · **Posted:** Thu Sep 18, 2008 3:49 am

First part of a class mapping is the identity specification.

Code:

<?xml version="1.0"?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Eg"
    namespace="Eg">

        <class name="Cat" table="CATS" discriminator-value="C">
****              
                <id name="Id" column="uid" type="Int64">
                        <generator class="hilo"/>
                </id>
****
                <discriminator column="subclass" type="Char"/>
                <property name="BirthDate" type="Date"/>
                <property name="Color" not-null="true"/>
                <property name="Sex" not-null="true" update="false"/>
                <property name="Weight"/>
                <many-to-one name="Mate" column="mate_id"/>
                <set name="Kittens">
                        <key column="mother_id"/>
                        <one-to-many class="Cat"/>
                </set>
                <subclass name="DomesticCat" discriminator-value="D">
                        <property name="Name" type="String"/>
                </subclass>
        </class>

        <class name="Dog">
                <!-- mapping for Dog could go here -->
        </class>

</hibernate-mapping>

graphicsxp · **Joined:** Thu Aug 14, 2008 5:31 pm **Posts:** 20

Thanks for the tip !

What if my database table does not define a primary key ( I know it shouldn't be) then can I not by-pass that in the xml file ?

Also, what if they are multiple primary keys ? How would that be defined in the xml file ? Can you give me a quick example ?

Thanks a lot for helping !

cremor · **Joined:** Tue Jul 29, 2008 3:30 am **Posts:** 74

If your primary key consists of multiple columns you use <composite-id> instead of <id>.
I don't think tables without a primary key can be mapped to an entity. I think you can only use the table as a component of another entity then. But I never tried this, so I might be wrong.

Look here for further information:
http://www.hibernate.org/hib_docs/nhibe ... aration-id

wolli · **Posted:** Thu Sep 18, 2008 4:16 am

Hibernate needs a primary key. If you don't have one, you can use a surrogate primary key. If you can't change your database then you have a problem.

What do you mean with "multiple" primary keys. If you mean a composite primary key, then check out this chapter of the docs:

http://www.hibernate.org/hib_docs/nhibernate/1.2/reference/en/html/mapping.html#mapping-declaration-compositeid

And I strongly recommend that you read some docs/books about hibernate before continuing. It will save you a lot of time.

Check out:

http://www.nhforge.org
http://www.manning.com/kuate/

graphicsxp · **Joined:** Thu Aug 14, 2008 5:31 pm **Posts:** 20

Thank you both for your help.

I meant a composite primary key indeed.

I agree with the fact I should read a book.... but I wish I could find one ! There's plenty about hibernate, but nothing about NHibernate. There is some online documentation, but I'm more of a 'book guy' :)

wolli · **Posted:** Thu Sep 18, 2008 4:58 am

Have a look at

http://www.manning.com/kuate/

That's the NHibernate version of "Hibernate in action". You can get the "early access edition". And since NHIberanate is a port you can take any hibernate book. You have to translate java to C# or VB but the principles are the same.

And you can try the reference doc for a start. It's not an easy start but there's a lot of valuable information in it. And browse through nhforge.

Here you can find a pdf version for 1.2:

http://www.hibernate.org/5.html#A27

I haven't found one for 2.0, yet.