[cx-oracle-users] Creating a large number of database connections

[Moore, P. <Pau...@at...>]

I have a program which needs to connect to a large number of
databases. Each connection is fairly short-lived (run a single SQL
query), but the connect times can be quite long, particularly as some
databases may be inaccessible due to network issues, and so there's a
long wait for timeouts.

What I'd like to do is to create all of my connections "in parallel",
and then run the queries as the connections are ready. This would
reduce the runtime of my application from the sum of all the connect
times (plus a fixed overhead) to the maximum connect time (plus a
possibly different fixed overhead).

At the moment, I'm doing this using multiple threads, but the extra
code needed to handle the threads, and to make sure that cursors are
only used from a single thread, is non-trivial. And there's also
Oracle's threading overhead.

Is there a simpler way of doing this, that I am missing? I need a
solution which will handle 100 or so connections, and will scale
reasonably sensibly. My initial thought was that some form of
non-blocking connect might work (I'm not an OCI expert), but when I
scanned the OCI manuals, it doesn't seem like OCI lets you do any
other database work while a nonblocking connect is in progress.

Can anyone suggest anything?

Thanks,
Paul Moore.