LITS: An Optimized Learned Index for Strings

Summary: LITS targets variable-length, skewed strings with a hash-enhanced prefix table plus per-node linear models and compact hybrid subtries, reducing learned-index last-mile costs. It outperforms HOT/ART by up to 2.43×/2.27× on point lookups while matching scan performance. (summarized by gpt-5.6-luna on Jul 24 2026)

Paper ID: 13740
Venue: VLDB
Year: 2024
Pagerank: 5.6675134e-05
Overall Rank: 7,224 | 50.44%
DOI: 10.14778/3681954.3682010

Incoming Non-self Citations Over Time

Authors

1. Yifan Yang (State Key Laboratory of Processors, Institute of Computing Technology, Chinese Academy of Sciences; University of Chinese Academy of Sciences)
2. Shimin Chen (State Key Laboratory of Processors, Institute of Computing Technology, Chinese Academy of Sciences; University of Chinese Academy of Sciences)

BibTeX Citation

@article{yang_vldb24,
        title = {{LITS: An Optimized Learned Index for Strings}},
        author = {Yang, Yifan and Chen, Shimin},
        journal = {PVLDB},
        series = {{VLDB} '24},
        volume = {17},
        number = {11},
        pages = {3415--3427},
        doi = {10.14778/3681954.3682010},
        url = {https://doi.org/10.14778/3681954.3682010},
        year = {2024}
}

Incoming Citations (Sorted by Pagerank)

Showing 7 of 7 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
10,262	LINE: A Learned Index with Group-Enhanced Leaves and Cache-Optimized Inner Tree	2026	SIGMOD	5.093636e-05
10,267	Mathematical Foundations of Poisoning Attacks on Linear Regression over Cumulative Distribution Functions	2026	SIGMOD	5.093636e-05
10,461	HIRE: A Hybrid Learned Index for Robust and Efficient Performance under Mixed Workloads	2026	SIGMOD	5.093636e-05
10,505	The Case For Language Model Approximated LIKE Predicate	2026	SIGMOD	5.093636e-05
10,617	LiBox: A Learned Index as an Array to Minimize Last-Mile Search	2026	VLDB	5.093636e-05
10,829	FB+-tree: A Memory-Optimized B+-tree with Latch-Free Update	2025	VLDB	5.093636e-05
10,955	DobLIX: A Dual-Objective Learned Index for Log-Structured Merge Trees	2025	VLDB	5.093636e-05

Outgoing Citations (Sorted by Pagerank)

Showing 10 of 10 cited papers.

Citations counted here include only citations to other VLDB/SIGMOD/CIDR/PODS papers in this database.

Rank	Cited Paper	Year	Venue	Pagerank
43	The Case for Learned Index Structures	2018	SIGMOD	0.00046060254
447	ALEX: An Updatable Adaptive Learned Index	2020	SIGMOD	0.00018322593
882	HOT: A Height Optimized Trie Index for Main-Memory Database Systems	2018	SIGMOD	0.0001342403
1,551	Updatable Learned Index with Precise Positions	2021	VLDB	0.00010381398
2,233	FINEdex: A Fine-grained Learned Index Scheme for Scalable and Concurrent Memory Systems	2022	VLDB	8.8968964e-05
2,806	Are Updatable Learned Indexes Ready?	2022	VLDB	8.1013097e-05
3,865	The Case for a Learned Sorting Algorithm	2020	SIGMOD	7.0621718e-05
4,300	DILI: A Distribution-Driven Learned Index	2023	VLDB	6.773869e-05
5,285	Order-Preserving Key Compression for In-Memory Search Trees	2020	SIGMOD	6.2821588e-05
5,954	When Tree Meets Hash: Reducing Random Reads for Index Structures on Persistent Memories	2023	SIGMOD	6.0292226e-05

Semantically Similar Papers

#	Overall Rank	Paper	Year	Venue
1	882	HOT: A Height Optimized Trie Index for Main-Memory Database Systems	2018	SIGMOD
2	10,262	LINE: A Learned Index with Group-Enhanced Leaves and Cache-Optimized Inner Tree	2026	SIGMOD
3	8,591	A New Paradigm in Tuning Learned Indexes: A Reinforcement Learning Enhanced Approach	2025	SIGMOD
4	2,648	On Effective Multi-Dimensional Indexing for Strings	2000	SIGMOD
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8	7,368	Accelerating String-key Learned Index Structures via Memoization-based Incremental Training	2024	VLDB
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