Oracle Index compression for range scan on file names
A new blog post on the Databases at CERN blog about tables storing long file names in a table, with full path, and index range scan on a prefixed pattern: https://db-blog.web.cern.ch/blog/franck-pachot/2018-11-oracle-index-compression-range-scan-file-names
COMPRESS ADVANCED LOW
The 12cR1 advanced index compression does not help here as all values are unique. Only partial prefix is redundant.
COMPRESS ADVANCED HIGH
The advanced algorithm ‘high’ introduced in 12cR2 can reduce better. But there’s no magic. Redundancy should be addressed at design. Full test: