Can you delete items from a Bloom filter?
Standard Bloom filters don't support deletion—unsetting a bit would break membership for other keys that need it. Counting Bloom filters track per-bit reference counts instead, allowing safe deletion, but use more space. For most use cases, append-only is acceptable.
Answered in
Bloom Filters: The One-Way Membership TestA probabilistic data structure: zero false negatives, tunable false positives. Check membership in RAM with bits instead of database queries.
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