Moving objects and datafiles around is required when you need to either change the physical location of the data files or when you want to migrate to ASM or some other Storage system. Up to now these operations caused the database to remain unavailable during the move activity. However in Oracle 12c this can be minimized to almost no downtime. Let’s look at how online table redefinition and datafile movement can help us in achieving zero downtime.
By default Oracle database does not log any DDL operations performed by any user. The default settings for auditing only logs DML operations. However that does not mean that you cannot do anything about it. Oracle has provided several ways by which you can track the DDL operations performed on the database. In this article we will look at two of the most common and easy to use ways.
Starting in Oracle 12c database, you can change this and enable the new Multithreaded configuration! And that too by merely setting one parameter. You can change the architecture by making Oracle database use thread based architecture instead of process based. Once changed, all Oracle processes will be threads within a few Oracle processes. Thus if CPU moves from one Oracle process to the other, the time between the context switch will be reduced significantly as the switching from one thread to the other is within the same process.
Oracle has come a long way from its inception of the 9i RAC database to its current 12c version. I remember the days when we had to deal with RAC related issues, ranging from performance to stability which gradually improved as this product matured. Learn more about the new feature now available with RAC .