Definition
Estimates the count of distinct items in ~KB, regardless of cardinality.
How it works
Counts billions of uniques (e.g. unique visitors) from hash-bit patterns; mergeable across shards.
Common questions
What is HyperLogLog?
Estimates the count of distinct items in ~KB, regardless of cardinality.
How does HyperLogLog work?
Counts billions of uniques (e.g. unique visitors) from hash-bit patterns; mergeable across shards.
What is HyperLogLog used for in system design?
Counts billions of uniques (e.g. unique visitors) from hash-bit patterns; mergeable across shards.
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