Hello,

I'm trying to get a better understanding on how transactions work. I'm running within JBoss and I have to separate datasources set up to different databases. What happens when I open up a transaction within a transaction? For example:

// get session to first datasource
Session sessa = factorya.openSession();

// get session to second datasource
Session sessb = factoryb.openSession();


Transaction transa = sessa.begintransaction();
Transaction transb = sessb.begintransaction();

// Test is table in db 1
Test ta = new Test("testing);
sessa.save(ta);

// Stuff is table in db 2
Stuff sa = new Stuff("stuff");
sessb.save(sa);

transa.commit();
transb.commit();

I was having a problem where I forgot to close transb and transa did not commit. I was thinking they would be seperate transactions to different datasources and a should not lock if we forgot to close b.

I didn't mention I'm running in JBoss. From what I understand the begintransaction() method uses the current transaction if one is open. It seems like that is happening here.

Shouldn't there be a way to make two transacitons completely separate for two different datasources? My sessions come from two different session factories that I setup for each datasource.

You say "forgot to close transb and transa did not commit". Could you be more precise here? By "forgot to close transb" do you mean that you didn't commit that transaction, that is, omitted the transb.commit() call? What precisely happened then, that is, what do you mean by "transa did not commit" ?

I did not commit transaction a. I had forgotten the call to trans.commit(). Transaction b was commited though but neither database was updated after the transb.commit(). I would have expected the database for transaction a to not update but I thought that transaction b would update since it was a different session factory for a second database.