Welcome to the Database Storage
Optimization blog – a blog covering the capabilities of the Advanced
Compression option, including: data,
index, network and backup compression as well as database compression tiering
and storage tiering.
But don’t worry; we’ll also discuss other
compression capabilities, such as Oracle’s Hybrid Columnar Compression (HCC).
Why start with the topic of the Advanced
Compression option compared to Basic Table Compression?
Well, because this is both a frequently
asked question – and a fundamental question regarding Oracle compression.
If you’re not familiar with Basic Table
Compression, then some important points to know about Basic Table Compression
are that it’s a free data compression capability and it is included with Oracle
Database Enterprise Edition.
More than a decade ago, Oracle Database 9i
Release 2 introduced Basic Table Compression, which compresses data that is loaded
using bulk load operations, but doesn’t compress data that is added/changed
through conventional DML operations (INSERT or UPDATE) – if INSERTS and UPDATES
are performed on a Basic compressed table/partition over time, then that
table/partition would have to be re-compressed to get the changes compressed.
This means that Basic Table Compression isn’t intended for OLTP applications,
and instead, is best suited for data warehouse applications (read-mostly) where
data is loaded using bulk load operations and is never (or very rarely)
So why is this important in relation to the
Advanced Compression option?
Well, for two important reasons.
The first is that the data compression
feature of Advanced Compression does ensure that DML changes are compressed. Oracle
Database 11g Release 1 introduced OLTP Table Compression, now called Advanced
Row Compression, which maintains data compression during all types of data
manipulation operations, including conventional DML such as INSERT and
The second reason, and an important part of
this Database Storage Optimization blog going forward, is that the Advanced
Compression option brings a number of database storage optimization
capabilities to the table, beyond just data compression, that folks often don’t
realize are available.
The Database Storage Optimization blog will
discuss all of these capabilities, so you know exactly what each capability
does, why you should care (and who knows, maybe for some you won’t care) as
well as provide some usage tips, tricks and best practices – and answer your
The capabilities that will be covered in
upcoming blogs include:
Data Guard Redo
And by the way, sorry about the delay in
new content (last
blog was March 2015), you’ll see much more activity from Andy and me in the
The database storage optimization adventure
continues in the next blog, in which we will discuss: Advanced Row Compression.