Any single hash will be suboptimal; the "magic" would be to use a bunch of different hashes to partition your space into suboptimal buckets, and use all of them

Any single hash will be suboptimal; the "magic" would be to use a bunch of different hashes to partition your space into suboptimal buckets, and use all of them at once to get very good (though still approximative) query results. This is what Spotify's excellent Annoy library does. [1] [1] https://github.com/spotify/annoy https://github.com/spotify/annoy