When to NOT use a database connection pool in Java?

Question

I can find many questions about how to use the connection pool and why it is a good idea, but I am wondering if this is really necessary.

I am creating a server application and although it is multithreaded, I was careful that only one thread ever accessed my database connection.

So, does it make sense to use a connection pool?

Can't I just open a connection to my database at the beginning of the life cycle and use this one connection forever, or will it be a timeout if it has been inactive for too long?

I really should call close()in my connection after something to do with him, or just call close()on ResultSetand / or Statement?

Answer 1

What is a database connection? This is a session with your database and as such:

• Session state of client and server sides
• There is a transaction associated with this session.

Now, since your client application is multithreaded, I suspect that there are only a very limited number of cases where your setup makes sense, namely:

• You are not using session state, even inadvertently (and this may be provider specific)
• You do not use transactions and always automatically execute
• Even with automatic fixation, there may be race conditions, so you make sure that this does not happen.
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