CODEWITHSUNDEEP
javahibernatejpahsqldb
HenryR
HenryR

Reputation: 8519

HSQLDB and Hibernate/JPA - not persisting to disk?

Something of an novice with HSQL and Hibernate...

em.getTransaction().begin();
for (Activity theActivity : activities) {
  em.persist(theActivity);
}
em.getTransaction().commit();
em.close();

followed by...

EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
System.out.println("QUERY:: "
    + em.createQuery("SELECT COUNT(*) FROM " + Activity.class.getName()).getSingleResult()
        .toString());
em.getTransaction().commit();

Prints 25000 (the number of Activity objects in activities). But when I run this test again, the number of objects in the count(*) doesn't increase (and is 0 at the beginning of the program). So the objects aren't getting durably written.

This is my hsqldb connection string:

name="hibernate.connection.url" value="jdbc:hsqldb:file:data/cmon"

so it's not an in-memory database as far as I know...

Does anyone have any ideas why the objects aren't getting persisted beyond a single JVM session? Happy to supply more information but there's so much state associated with Hibernate / JPA / HSQL that it's not clear exactly what is pertinent.

Upvotes: 26

Views: 24281

Answers (6)

Pradeep
Pradeep

Reputation: 97

Closing sessionfactory worked for me.

Upvotes: 1

Kaushik Lele
Kaushik Lele

Reputation: 6637

I was using HSQL DB version 2.2.5. I tried above approaches i.e. setting shutdown=true and hsqldb.write_delay=false It did not work. As suggested in some blog, I added statement

org.hsqldb.DatabaseManager.closeDatabases(0);

after transaction commit. But it did not work.

HSQL DB version 2.2.9 seems better than this. With one workaround it solves this problem. To handle above problem take following steps :-

1) hsqldb.jar from lib of HSQL DB version 2.2.9

2) In hibernate config xml just specify URL I am using HSQL file-based database. 

 <property name="hibernate.connection.url">jdbc:hsqldb:file:D:\JavaProj\TmpDBLocation\myKauDB</property>

3) In your program at the end write statement 

org.hsqldb.DatabaseManager.closeDatabases(0);

Now run the hibernate program that commits the data to DB.

Check HSQL DB by opening it in standalone mode and with URL 

jdbc:hsqldb:file:D:\JavaProj\TmpDBLocation\myKauDB

You should see your changes persisted in DB.

Upvotes: 4

Jean-Luc
Jean-Luc

Reputation: 41

Simply close your EntityManagerFactory with HSQL in filemode, after the commit to really persist datas...

Upvotes: 4

Maciek Kreft
Maciek Kreft

Reputation: 892

The solution is :

<property name="dialect">org.hibernate.dialect.HSQLDialect</property>

in hibernate.cfg.xml

This is rest of my configuration:

Libs:

  • HsqlDb 2.0.0
  • Hibernate 3.5.6

Url:

<property name="connection.url">jdbc:hsqldb:file:data/mydb;shutdown=true;hsqldb.write_delay=false;</property>

Upvotes: 9

Pascal Thivent
Pascal Thivent

Reputation: 570285

Does anyone have any ideas why the objects aren't getting persisted beyond a single JVM session?

HSQLDB doesn't write changes immediately to disk after a commit (see "WRITE DELAY"), HSQLDB is not Durable by default (that's from where "performances" are coming from).

Either try to set the connection property shutdown=true in the connection string to get the changes written when the last connection will end.

jdbc:hsqldb:file:data/cmon;shutdown=true

If it doesn't help, try to set the WRITE DELAY to 0 (or false). If you're using HSQLDB 1.8.x, use the SQL command:

SET WRITE_DELAY 0

If you're using HSQLDB 2.0.x, you can now also use a connection property hsqldb.write_delay: 

jdbc:hsqldb:file:data/cmon;hsqldb.write_delay=false

Upvotes: 30

Chris Lercher
Chris Lercher

Reputation: 37778

Did you set hibernate.hbm2ddl.auto to create-drop in your persistence.xml? This drops your tables and re-creates them on every startup.

You can set it to update instead, or if you want to manage the schema yourself, then set it to validate.

Upvotes: 8

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