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Oracle Option: Advanced Compression

Oracle Advanced Compression complements Enterprise Edition basic table compression feature with comprehensive data compression and Information Lifecycle Management capabilities, including those specifically tailored to Oracle's engineered systems, like Oracle Exadata.
Oracle advanced compression promises to

Compression algorithm

Database block level (Advanced Row Compression?)

The compression algorithm replaces duplicate values within a database block with a refernce to a symbol table in the same block which contains the actual (duplicated) value.
The benefit of storing the symbol table in the same database block is that no IO costs are involved when resolving a reference.
This strategy is assumes that OLTPs and datawarehouse applications have lot of duplicate values in a database block.

Features

Advanced Row Compression Used for structured data
Advanced LOB Deduplication and Compression Used for unstructered data
Advanced Index Compression
RMAN and Data Pump compression Database backups
Advanced Network Compression Compression of data transferred between database and application.
Data Guard redo log transport Compression Network

Heat maps

A heat map records data modification times at row and segment level and access time at segment level.
These statics can then be used to automaticaly compress and move data base using the declarative language of automatic data optimization (ADO).

Compress existing tables

Existing table can be compress with

Estimating compression ratios

Before compressing existing tables, it might be worthwile to estimate their compression ratio with dbms_compression (also referred to as compression advisor).

Flashback Data Archives

Advanced Compression also optimizes storage requirements for history tables in Flashback Data Archives when using them to track transactional changes.

See also

Oracle database options

Links

Oracle Advanced Compression FAQ

Index