Note: this article covers simple compression. Oracle introduced in version 11g release 2 a new feature called Advanced Compression which is not covered here.
General principle of Oracle compression
Oracle compression is a way of reducing the d…
Have you ever had to make fundamental changes to a table in Oracle, but haven't been able to get any downtime? I'm talking things like:
* Dropping columns
* Shrinking allocated space
* Removing chained blocks and restoring the PCTFREE