Oracle Advanced Compression provides a comprehensive set of compression capabilities to help improve performance and reduce storage costs. It allows organizations to reduce their overall database storage footprint by enabling compression for all types of data: relational (table), unstructured (file), index, network, Data Guard Redo and backup data. Although storage cost savings and optimization across servers (production, development, QA, test, backup and etc...) are often seen as the most tangible benefits, additional innovative technologies included in Oracle Advanced Compression are designed to improve performance and to reduce CapEx and OpEx costs for all components of an IT infrastructure, including memory and network bandwidth as well as heating, cooling and floor-space costs.
The compression ratio achieved in a given environment depends on the data being compressed, specifically the cardinality of the data. In general, organizations can expect to reduce their storage space consumption by a factor of 2x to 4x by using Advanced Row Compression. That is, the amount of space consumed by uncompressed data will be two to four times larger than that of the compressed data.
Advanced Row Compression has no adverse impact on read operations. There is additional work performed while writing data, making it impossible to eliminate performance overhead for write operations. However, Oracle has put in a significant amount of work to minimize this overhead for Advanced Row Compression.
The benefits of Advanced Row Compression go beyond just on-disk storage savings. One significant advantage is Oracle’s ability to read compressed blocks directly without uncompressing the blocks. This helps improve performance due to the reduction in I/O, and the reduction in system calls related to the I/O operations. Further, the buffer cache becomes more efficient by storing more data without having to add memory.
Due to RMAN’s tight integration with Oracle Database, backup data that is already compressed by Advanced Compression remains compressed when it is written to disk or tape and doesn’t need to be uncompressed before recovery – providing an enormous reduction in storage and a potentially large reduction in backup and restore times.
No application changes are required to implement data compression with Advanced Compression.