The X$ Tables (Advanced DBA)
Why do people climb mountains? Because they are there! Why do people open the hood of their car and look at what’s inside? Because they can! Why do DBAs look at the X$ tables? Because they are there and they can!
Oracle now has 945 X$ tables, and they are the last frontier for the expert DBA to explore and analyze the deepest cavern of the Oracle database. Querying the X$ tables can give secrets to undocumented features and parameters, information about future Oracle versions, and shorter or faster routes ...