A Versioned Unified Graph Index for Dynamic Timestamp-Aware Nearest Neighbor Search

Jun Woo Chung; Weijie Zhao

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arXiv · 2608.27663

A Versioned Unified Graph Index for Dynamic Timestamp-Aware Nearest Neighbor Search

Jun Woo Chung·Weijie Zhao

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Abstract

We present TiGER (Time-Integrated Graph for Efficient Retrieval), a novel approach for performing fast time-aware approximate nearest neighbor searches on dynamic vector datasets with flexibility over any possible time range. Our proposed algorithm builds and maintains a unified graph for all vectors by leveraging an index structure based on integrated versioned connectivity, allowing arbitrary time intervals to be queried directly on the unified graph without having to traverse invalid vectors. This forgoes the need for post-search filtering or merging, or separate graphs for each possible composite range. Empirical evaluations show that our method attains up to a 5x improvement in queries per second (QPS) without compromising accuracy over baselines based on filtering or per-time-segment sub-graphs. We believe that this method will enable efficient temporal analysis across evolving datasets in real-time recommendation systems, log analysis, and any scenario requiring fast similarity search over dynamic, time-segmented data.

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Jun Woo Chung, Weijie Zhao. 2026-08-27. A Versioned Unified Graph Index for Dynamic Timestamp-Aware Nearest Neighbor Search. https://arxiv.org/abs/2608.27663

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