Look around in conf/log4j.properties
In particular the root category which you can adjust to get more or less debug
log4j.rootCategory=DEBUG, Default, Console
In addition most jdbc drivers have an optional logging mode you can turn on in the connection string. You might like to check this out for whichever driver you are using
> I would like to see the name of the column when there
> are exceptions like:
> ...(java.sql.SQLException: ORA-00904: invalid column
> How can I turn this on?
I don't think you can - this is a limitation of Oracle's thin drivers. AFAIK they won't give you the column name. You have to paste the equivalent query into SQL-PLUS or a similar tool and execute it form there.