Data Structures22 min read

Bloom Filter Concept

Understand bloom filters for memory-efficient membership checks with possible false positives.

David Miller
September 28, 2025
5.0k175

Bloom filter tells:

  • item is definitely NOT present
  • or MAYBE present

Why useful

  • huge datasets
  • save memory

Graph

flowchart LR
  A[Item] --> B[Hash1]
  A --> C[Hash2]
  B --> D[Bit array]
  C --> D

Remember

  • no false negatives
  • possible false positives
  • used in databases and caches
#Python#Advanced#Probabilistic