Re: Optimizer "enhancements" in 19.9?

I see that Mikhail has supplied the explanation - and may have taken advantage of a Q&D I often use as the 2nd step to avoid looking too closely at a 10053
( https://jonathanlewis.wordpress.com/2014/05/14/feature-bypass/ )

grep -n -i bypassed {10053 tracefile name}

Also - for pre-emptive discovery from the executable - always check for new bypasses:

strings -a oracle.exe | grep -i bypassed >bypassed.txt

The interesting thing now is to see if it's possible to come up with an example where the bypass is necessary to avoid getting wrong results
(because that's presumable why it's been introduced) and then to watch
newer versions to see if the restriction is gradually relaxed.

Regards
Jonathan Lewis

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