This trace has been around for quite a while. I’m not sure when it first showed up but easily back to Oracle8i.
This is a companion discussion topic for the original entry at https://blog.toadworld.com/sql-tuning-a-close-look-at-the-10053-cbo-trace
This is a companion discussion topic for the original entry at https://blog.toadworld.com/sql-tuning-a-close-look-at-the-10053-cbo-trace