Does JE support key prefixing or key compression?
Key prefixing is a database storage technique which reduces the space used to store B-Tree keys. It is useful for applications with large keys that have similar prefixes. JE supports key prefixing as of version 3.3.62. See DatabaseConfig.setKeyPrefixing. JE also does not currently support key compression. While we have thought about it for both the DB and JE products, there are issues with respect to the algorithm that is used, the size of the key, and the actual values of the key. For example, LZW-style compression works well, but needs a lot of bytes to compress to be effective. If you’re compressing individual keys, and they’re relatively small, LZW-style compression is likely to make the key bigger, not smaller.
