Bryan Pendleton wrote:
To commit your transaction, you need to call Connection.commit() (or put
your connection into auto-commit mode). Closing your result sets is
desirable, but by itself it won't commit the transaction.
But it will commit if the connection is in auto-commit mode, right?
I've now gone through the whole of my code making sure all the places
where I turn off autocommit have a finally block to commit and then
turn it back on again, and I now close my result sets even when empty.
If I'm correct above, this *should* do the trick...
You should also close your statements when you no longer need them. Derby
has finalizers for ResultSet, Statement, and Connection objects, but
waiting for the Java garbage collector to collect your JDBC objects can
be very problematic, as they can accumulate quickly and can hold quite
a bit of resources. So it's good to keep in the habit of closing them
as soon as possible.
OK; lots more try/finally blocks needed, then!
One thing I find: all this manual closing doesn't half complicate the
code! It's a bit like going back to C++... :-(
Another thing you can do is to configure the transaction's isolation level;
the default isolation level holds a lot of locks, and many applications
find that they can run successfully using a lower level of isolation.
Hmm, maybe also worth a try. I'd better get it working first though!
Many thanks for your advice, yet again!
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John English | mailto:[email protected]
Senior Lecturer | http://www.it.bton.ac.uk/staff/je
School of Computing & MIS | "Those who don't know their history
University of Brighton | are condemned to relive it" (Santayana)
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