Definition
A probabilistic, multi-layered data structure that enables O(log n) search and insertion in vector database metadata indices; it trades increased memory consumption for significantly faster dynamic updates and concurrent access compared to balanced trees.
It is not a list of items to 'skip' or ignore, but rather a multi-level shortcut system for faster data traversal.
"An express train system where the bottom track stops at every station, but higher tracks skip multiple stations to reach the destination faster."
- HNSW (Hierarchical Navigable Small World)(Prerequisite (HNSW is essentially a multi-layered skip list for high-dimensional vectors))
- Postings List(Component (Skip lists are often used to optimize the intersection of postings lists in RAG filtering))
- Metadata Filtering(Application (The primary use case for skip lists in RAG to prune search results))
Conceptual Overview
A probabilistic, multi-layered data structure that enables O(log n) search and insertion in vector database metadata indices; it trades increased memory consumption for significantly faster dynamic updates and concurrent access compared to balanced trees.
Disambiguation
It is not a list of items to 'skip' or ignore, but rather a multi-level shortcut system for faster data traversal.
Visual Analog
An express train system where the bottom track stops at every station, but higher tracks skip multiple stations to reach the destination faster.