Hibernate version:2.1.7c, 24.11.2004

Mapping documents:
<hibernate-mapping>
<class name="mypackage.X12Transaction"
table="TRANSACTION"
dynamic-update="true"
dynamic-insert="true">
<id name="id" type="long" column="TRXID" unsaved-value="null">
<generator class="sequence">
<param name="sequence">CSRSEQUENCE</param>
</generator>
</id>
<property name="userId" column="TRANSUSERID" type="integer"/>
<property name="transactionPerformed" column="TRANSPERFORMED" type="string"/>
<property name="transactionStatus" column="TRANSSTATUS" type="string"/>
<property name="transactionDate" column="TRANSDATE" type="java.util.Date"/>
<property name="transactionIdentifier" column="TRANSIDENTIFIER" type="string"/>
<property name="x12In" column="X12IN" type="java.sql.Clob"/>
<property name="x12Out" column="X12OUT" type="java.sql.Clob"/>
</class>
</hibernate-mapping>


Name and version of the database you are using: oracle 10g

In the table TRANSACTION, when we first insert a record into the table X12IN column gets populated along with others. X12OUT is not populated in the insert. So far so good, this part worked fine.

some processing happens then I get the x12out data.

Now I am trying to update the record by updating the X12OUT column. The update call wipes out the X12IN column. When I am passing the X12Transaction instance to the update, I think the X12IN is not present.

My question is how can I update only the X12OUT field. Here I know the TRXID, so like in plain JDBC I can accomplish this with the sql query like:

UPDATE TRANSACTION
SET X12OUT = ?
WHERE TRXID =?


How can I achieve the same in hibernate? I bought the e-book hibernate in action, which chapter specifically addresses this?

Any help will be much appreciated.

TIA

Rumpa Giri

Found one way to do it, I am sure there is another way.

When I load the record by id by doing the following and then calling update, the generated sql is what I am looking for.

x12 = (X12Transaction) session.load(X12Transaction.class, new Long(_id));

Then update call results in:

Hibernate: update TRANSACTION set X12OUT=? where TRXID=?

The load by id, does that makes a select call?

In that case is there a way to do the column update only without the overhead of the select sql?

TIA
Rumpa Giri

It might if the an object with that identity has not already been loaded, or is not in the cache.



When Hibernate loads an object, it must load all of it's properties. Otherwise, the object would be left in a strange state.

The new UPDATE command (planned for Hibernate3) will be able to update a single property of an object, but of course this kind of change will not be reflected in the objects in the current session for the very same reason.

Thank you for your reply.

I will read more about cache then.

Thanks again,
Rumpa Giri