Hibernate treats Transient object as persisted object?

jeusdi2 · **Joined:** Sat Apr 07, 2007 6:53 am **Posts:** 16

Hello All, I have a problem. I have a Customer with a Bank_Address that inherites from Address Class. When I create a new customer and new bank_address transient objects.

Code:

           Customer customer = new Customer("2", ...);
           customer.setBank_Address(new Bank_Address(...));

and save them calling save method of session as follow:

Code:

             session.save(customer);
             session.Flush();

This code crashes because hibernate insert customer, but later, it try update a bank_Address, as if it already was a persisted object.

SQL LOG-->

Quote:

Hibernate: INSERT INTO CUSTOMER (FIRST_NAME, SECOND_NAME, BANK_ADDRESS, ID) VALUES (@p0, @p1, @p2, @p3); @p0 = 'Jordi', @p1 = 'Cabré Roca', @p2 = '2', @p3 = '2'
Hibernate: UPDATE ADDRESS SET STREET = @p0, NUMBER_STREET = @p1, CITY = @p2, STATE = @p3 WHERE ID = @p4; @p0 = 'La Parra', @p1 = '15', @p2 = 'Riudecols', @p3 = 'Tarragona', @p4 = '2'

<-------> In this point program crashes, becaus in database this bank_address doesn't exist.
if code doesn't crashes the follow sentence is UPDATE BANK_ADDRESS ...

the correct SQL sentences should be:
INSERT INTO CUSTOMER(...)
INSERT INTO ADDRESS(...) instead of UPDATE ADDRESS SET(...)
INSERT INTO BANK_ADDRESS(...)

What Do I do wrong?

thanks in advanced.

Mapping files -->

Code:

   <class name="Customer" table="CUSTOMER">
      <id name="Id" column="ID" type="String">
         <generator class="assigned" />
      </id>
                ...
      <many-to-one name="Bank_address" class="Model.BankAddress, ComponentsBroker" unique="true" cascade="all" column="BANK_ADDRESS" />
                 ...
   </class>

   <class name="Address" table="ADDRESS">
      <id name="Id" column="ID" type="String">
         <generator class="assigned" />
      </id>
      <property name="Street" type="String" column="STREET"/>
      <property name="Number_street" type="String" column="NUMBER_STREET"/>
      <property name="City" type="String" column="CITY"/>
      <property name="State" type="String" column="STATE"/>
      
      <joined-subclass name="BankAddress" table="BANK_ADDRESS">
         <key column="ADDRESS_ID"/>
         <property name="BankName" type="String" column="BANK_NAME"/>
         <property name="Account" type="String" column="ACCOUNT"/>
      </joined-subclass>
      
      <joined-subclass name="Model.ContactAddress, ComponentsBroker" table="CONTACT_ADDRESS">
         <key column="ADDRESS_ID"/>
         
         <component class="Name" name="ContactName">
            <property name="First_name" column="FIRST_NAME" type="String"/>
            <property name="Second_name" column="SECOND_NAME" type="String"/>
         </component>
         <property name="Phone" type="String" column="PHONE"/>
      </joined-subclass>
   </class>

jeusdi2 · **Joined:** Sat Apr 07, 2007 6:53 am **Posts:** 16

I've found other forum item in 2005 that talked about the same problem.

http://saloon.javaranch.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=78&t=000071

In these thread they told the problem was "assigned" id generator. they said Hibernate assumes that if an object has an id (different from 'null' or from the 'unsaved-value'), then it's an existing DB record.

And here appear two problems:

* What about entyties that id are natural keys (social security number, ...)
* Why my customer is saved so? its id is assigned = '2' and id is diferent of null.

Can you help me to see some light? Any help would be great appreciated.

Thanks

batmat · **Posted:** Sun Apr 15, 2007 3:26 pm

In fact, Hibernate needs a way to know if an entity is already persisted or still only in memory (for example, to know if an insert or an update is needed).

To manager this, it's recommended to use surrogate keys, not business/natural one.

Apart from this, I guess your mapping maybe just misses an unsaved-value="null" attribute (although this is the default, imo...). This would tell hibernate that if getId() returns null, then it's not been persisted yet, see ?

jeusdi2 · **Joined:** Sat Apr 07, 2007 6:53 am **Posts:** 16

Ok thanks for your help, however, why to save customer generates a INSERT instead of UPDATE? If I follow your words, customer object should be updated because your id= '2'. Why the customer is inserted and bank_address is updated?

When I execute session.save(customer) hibernate generates a INSERT CUSTOMER. According to your words hibernate should generate a UPDATE CUSTOMER.

Thanks for all.