See https://github.com/cwida/fsst

FSST is a compression scheme focused on string/text data: it can compress strings from distributions with many different values (i.e. where dictionary compression will not work well). It allows random-access to compressed data: it is not block-based, so individual strings can be decompressed without touching the surrounding data in a compressed block. When compared to e.g. LZ4 (which is block-based), FSST further achieves similar decompression speed and compression speed, and better compression ratio.