Which columns are rely tracked by oracle to grantee write consistency and if needed trigger a DML restart when using the default statement-level consistency ?
Sometimes you may see strange ,unexpected behavior and write consistency bugs because not all the columns that are supposed to be tracked ,are really tracked !
Just check the following articles :
A bug from 2011 (still there in 18c) : http://db-blog.web.cern.ch/blog/franck-pachot/2018-09-oracle-write-consistency-bug-and-multi-thread-de-queuing
A Bug from 2006 (still there in 12.2) : http://blog.sqlora.com/en/merge-and-ora-30926-part-2-or-differences-in-write-consistency-between-update-and-merge/
So how to know it the columns that are supposed to be tracked really are ? I’m going only to treat UPDATE and MERGE statement here.