The most important thing for a Database Administrator is to understand the Oracle architecture. By understanding architecture I mean that any point of time, at any step, at any command, you should have a clear idea which process is doing it, which shared memory its using.

Oracle is all about PROCESS & SHARED MEMORY, once you understand that in depth you need not have to separately learn how to perform backup & recovery, how to approach a performance issue etc.

Hence in the subsequent posts I’ll try to explain the architecture and internals of Oracle in as simple way as I can, however the complexity of architecture would make that a difficult job for me, but try to order my posts in the sequence which makes it all as a story.

Throughout the post, I am requesting each of my reader to focus on Process and Memory, if I forget to cover that which process is doing it or from where it is getting the memory to do it, please feel free to comment and ask or if I am not aware of, please comment and tell.

1. Oracle Process Architecture Internals
2. Oracle Memory Architecture Internals(SGA & PGA)
3. How to Interpret an Explain Plan
4. What is a Full Table Scan (FTS) in Oracle
5. Index Lookup (Unique Scan,Range Scan, Full Scan, Fast Full Scan, Skip Scan)
6. Oracle Memory Architecture Internals(SGA & PGA)
7. Direct Path Reads
8. Table Access by Rowid
9. Index Unique Scans
10. Index Range Scans
11. Index Full Scans
12. Index Fast Full Scans
13. Index Skip Scans
14. Direct Path Read/Direct Path Read Temp – Oracle Wait Event