Hibernate caches queries an give obsolete data back

alioum · **Joined:** Fri Oct 22, 2004 4:00 pm **Posts:** 5

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Hibernate version:2.1.7

Mapping documents:

Code between sessionFactory.openSession() and session.close():

Full stack trace of any exception that occurs:

Name and version of the database you are using:Oracle 9i EE

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:

Hi Folks,
I hope someone can help me with the following problem.

I am using the following query to get users by their status from the database:

<query name="RmsBenutzer.findByStatus">
<![CDATA[
from RmsBenutzer u where u.status = :status order by upper(u.login)
]]>
</query>

I get the userlist without any problem. Now when I change a user attribute (let's say his firstname) and query the database again, i get alternatively the previous and the new value. The new value is saved to DB without any problem.
When i change the value(firstname) four times for example, the following queries return one of the four values randomly.

I played with the cache issues to solve the problem with out any success.

I tried this too:

Code:

Session sess = SessionFactoryHelper.getCurrentSession();
Query q = sess.createQuery("from RmsBenutzer where status = "+status.intValue()+" order by upper(login)");
q.setCacheRegion("CacheRegionOfTheRMSUserList");
         q.setForceCacheRefresh(true);         
         List testuserlist = q.list();
         sess.flush();

without any success.

For Information my application is running on SAP WAS and i am using the
DB-Connection through a datasource.

Thank you for nay help.

Alioum

jt_1000 · **Posted:** Tue Mar 28, 2006 1:08 pm

if you are requerying through the same "session" object, and not updating through that same "session" object, then your experience is consistent with how hibernate works.

If you are "updating" via, 3rd party tool, like TOAD or SQLPLUS or any command line tool, then your experience is consistent with how hibernate works - regardless of your cache settings. You need to invalidate the cache - close your session and in your sessionfactory call evict methods to clear out the cache for the objects that changed.

Also, notice that if you are worried about concurrent updates to the same object, then you should setup "versioning" on your objects. Look into the "<version...>" tag on your class mapping.

jt_1000 · **Posted:** Tue Mar 28, 2006 1:10 pm

one last thing is that you may be issuing "session.save" vs. session.saveOrUpdate on your objects - and make sure your unsaved-values="null" on your PK. This might explain the "insert" of a new record vs. an update of existing...

alioum · **Joined:** Fri Oct 22, 2004 4:00 pm **Posts:** 5

Hi jt_1000,
thx for your wonderful help. I just closed the session after querying the list and it worked!!!!
here are the 3 lines which make me smile...

Code:

sess.flush
sess.clear();
sess.close();

have a nice day

[quote="jt_1000"]if you are requerying through the same "session" object, and not updating through that same "session" object, then your experience is consistent with how hibernate works.

If you are "updating" via, 3rd party tool, like TOAD or SQLPLUS or any command line tool, then your experience is consistent with how hibernate works - regardless of your cache settings. You need to invalidate the cache - close your session and in your sessionfactory call evict methods to clear out the cache for the objects that changed.

Also, notice that if you are worried about concurrent updates to the same object, then you should setup "versioning" on your objects. Look into the "<version...>" tag on your class mapping.