Oracle Dictionary fragmentation

The purpose of this post is mainly to highlight the performance degradation due to dictionary index fragmentation. It is something that oracle not widely announce but it came from the physical structure of the database.

Oracle databases have the AGE and the age mainly came from the number of DDL (more...)

NOLOGGING in numbers

Hi All
I have made small investigation about redo generation. From early days of my career I was remember that nologging operation is very performance effective but never try to quantify this very.
Every application can theoretically be split into 4 groups of tables (I use my personal names but (more...)

Column Encryption tricks

This story starts when someone ask me to Look on Transparent Data Encryption issue. We discover that we could not do Partition Exchange due to the difference in encryption keys on the involved table columns. It have clear common sense to bring them in sync thus we happy trying to implement Oracle Recommendation (Unable To exchange A Partition With A Table If It Has An Encrypted Column [ID 958728.1]) using the following scripts.

ALTER TABLE TESTTBL MODIFY (COL1 decrypt);
ALTER TABLE TESTTBL MODIFY (COL1 encrypt using '3DES168' identified by "MyKey2013");
ALTER TABLE TESTTBL MODIFY (COL2 decrypt);
ALTER TABLE  (more...)