performance - Using hashes as IDs in key-value stores -

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i'm wondering whether idea use hashes (cityhash, murmur , like) keys in key-value store hazelcast. i'm expecting have 2,000,000,000 records (urls) in database, collisions happen. wouldn't super critical lose data through hash collisions, of course best avoid them.

a record contains url, time stamp, status code. main operations inserting , looking whether url exists.

so, suggest, given speed relevant:

  • using id generator, or
  • using hash algorithm cityhash or murmur, or
  • using relevant string, url in case, itself?

hazelcast not rely on hashcode/equals methods of key object, instead using murmur hash of binary representation of key.

in short, should not worry hash collisions.


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