Basically the connection to the database server stays open until the timeout in the admin, so the authenticate piece of the communication to the database doesn't have to be performed each time.
So you want to enable this, which is the default.
Not sure what the specific error is; however CF will drop all of it's DB connections on restart (graceful or not).
This seems like a good resource for oracle errors: http://www.ora-error.com/
The error you have seems like a max cursor error, so maybe CF fired off something and was still running after the restart. What was the cf restart reason? If it was stalled maybe the code is firing something off and doing some bad things. Have you seen the issue since or just on CF restart? How about the Oracle logs, do they indicate anything?
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