Do we have a way to check if an element already exists in HyperLogLog in Java

Question

I have a use case where I need to check if an element already exists in the Hyperloglog and if not, I need to make a hbase call. Do we have any method IN JAVA to check if element already exists in HyperLogLog

private static HLL hllActiveUsersWithPID = new HLL(14,5); HashFunction hashFunction = Hashing.murmur3_128(); This is the use case — Pranjal Tripathi, Nov 22 '21 at 14:58
Is that a library you're using? https://github.com/aggregateknowledge/java-hll — geobreze, Nov 22 '21 at 15:01
You can add an element and check whether cardinality has changed or not. If it changed, then HLL didn't contain this element — geobreze, Nov 23 '21 at 09:04

score 1 · Answer 1 · answered Nov 23 '21 at 09:24

1

HyperLogLog is not suitable for checking element memberships. Use a Bloom filter, if you need a compact data structure for approximative set membership testing. More recent, but more complicated alternatives would be Cuckoo, XOR, or Ribbon filters.

answered Nov 23 '21 at 09:24

otmar

386
1
9

Do we have a way to check if an element already exists in HyperLogLog in Java

1 Answers1