Search in Oracle Bank losing session

Question

Good morning dear friends,

i am having serious problems regarding using Oracle database and losing session. The scenario is as follows: of thousands that you want to accomplish, some of them crash and when we see if it is still running, they no longer exist in the bank. This happens both in SQL Developer and in the Java application itself. This error seems to happen within 1% of many that run. One thing I realized, is that the larger the volume of data to be worked on in the query, the more often the error happens. The most interesting thing is that both SQL Developer and the application are waiting for an answer from the database, even without a session in the database. If I take this query and try to run again, it runs normally.

These queries rotate 7 in parallel, returning from seconds to a few minutes. If you are already running more than 30 minutes, you have surely missed the session.

I’m sorry if the question is vague, but I couldn’t find any pattern for you to express here. I would like to know the possible causes to help in this investigation.