Hi Jim,
I sent an email reply to this query yesterday, but it doesn't seem to have appeared yet - maybe it's still in moderation somewhere.
There are a number of reasons why your connections are dropping out:
- The network is configured (or mis-configured) with at least on switch, router or firewall having a time to live (TTL) setting;
- The network has a faulty component somewhere;
- The database login uses a profile which has an IDLE_TIME set to log you out (and rollback etc) after a given time of idleness (or thinking!);
- Windows 7 and higher, has a feature whereby it will disconnect the WiFi network connection after a period, to save power. This only applies if you are on WiFi of course, but it has affected me in the past.
I have suffered from most of the above in the past, I think I've only missed out on the faulty network component.
If the network is mis-configured then your network team will need to find it and fix it. If the database login is affected by a profile, then good luck getting that changed as it could be an instruction from "on high" to keep the database clean of idle sessions.
Until the network team get their act together (and I'm speaking from experience) your workaround is to set the "SQLNET.EXPIRE_TIME" to a small number of minutes, say 15, in the sqlnet.ora on the database server. That will send a probe from the database to keep any open connections working, while getting rid (or helping) those that are definitely dead connections.
In my last contract I suffered from a switch being configured with a 15 minute idle time. That's fine, but if I submitted a long running query (and one I was optimising took 54 minutes originally) then while Oracle was still working, the network dropped my connection, resulting in an inability to test any changes, plus a lot of "interesting Scottish Swearing". SQLNET.EXPIRE_TIME was set to a time (in minutes) less than the 20 minutes that they had set - I used 15. That stopped the problem and when I finished that contract, the network team still had not changed the setting!
Obviously you need to set this less than the timeout you are suffering from.
It is unlikely to be Toad, however, you can go to View -> Toad Options and do a search for delay, timeout, network etc, and see if there are some settings that might be being used in the GA version of Toad that may not have been used in the evaluation version that you used previously.
HTH