java work

Fighting with transactions in weblogic & oracle

Here is what I've been fighting with and has been causing me great frustration: java.sql.SQLException: ORA-01555: snapshot too old: rollback segment number 1 with name "PURGERBS1" too small The segment is set right after obtaining the connection using oracle-specific SQL

What this means is that the rollback segment is too small for the queries I am running on the database (we're copying blobs...). The code is using straight SQL on a connection to an oracle DB obtained from the weblogic EJB container.
We can live with only part of the data being actually treated because we'll get an error and it's stil better than nothing (we are cloning data basically)

Ok... easy then I'll just mark the method where all this is done as NotSupported in the deployment file... still won't work. Oh... but that's because Oracle only support Read Commited and Serializable ! Duh... thanks for making me believe I could make a bean method work outside of transactions !

Ok... so I'll try to set the connection isolation... of course I can't because I can't set it to None and because the container will just ignore it anyway I think

Next idea is to make the bean method handle the transaction and commit every so many queries, but I can't get a UserTransaction object unless the whole bean is made BMT which I do not want to do.

Humm.. I'm sure this is bad but perhaps I can just call commit() on the connection object I get from the container. Surprise surprise... it doesn't shout or yell but it crashes the same way on a different rollback segment... X-files as far as I'm concerned

I've run out of ideas so I will just un-optimize the code and get a new connection and statement for every add and remove I make.

Or maybe I'm just suffering from the sizzling heat in Paris and can't think straight ?

Posted by pgirolami76 at June 26, 2003 01:57 PM | TrackBack