There are three major components without which any computer cannot operate.
- Processor / CPU
The major feature of memory is speed; it is very fast. That means it can process many operations within a short period of time (1000 times faster than operations done in storage). Another characteristic is that it is not permanent. Anytime you restart a computer your memory is flashed out (erased).
If an application wants to do any kind of processing with data, it cannot access directly the data on the storage. The only layer accessible for a processor is the memory. Thus, if you need to work with data, they have to be in the memory first.
The characteristics of storage is that is permanent, which means that even after you reboot a computer or server you can still find your data there. On the other hand, operations doing on your storage are very slow.
Oracle and all other databases work the same 🙂 Let’s have a closer on memory and storage structures in Oracle in my next article “Instance and Storage“