Prior to Oracle 12c, if you wanted to move a database’s file, you either had to shutdown the database, or take the datafile/tablespace offline. Here is an example of the steps you might take:
I’ve been meaning to write something up on Oracle 12c’s new Adaptive Plans. When I do have poorly performing SQL statements, it seems that the issue is often due to bad optimizer stats. Recalculate the stats and performance is improved. I like the new 12c feature of Adaptive Plans where the database engine will reformulate the execution plan on-the-fly if it determines the intial plan is suboptimal.
Here is a nice video from Oracle Corp featuring Tom Kyte on this new 12c feature.