Lemo: A Cache-Enhanced Learned Optimizer for Concurrent Queries

Summary: Lemo is a cache-enhanced learned optimizer for concurrent multi-query workloads. A shared buffer caches subquery results with a replacement policy, leveraging cached data to guide plan generation in PostgreSQL. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: h893c634ef239e106
Venue: SIGMOD
Year: 2023
Pagerank: 5.9957692e-05
Overall Rank: 5,776 | 61.18%
DOI: 10.1145/3626734
PDF: Download (CC BY 4.0)

Incoming Non-self Citations Over Time

Authors

1. Songsong Mo (Nanyang Technological University)
2. Yile Chen (Nanyang Technological University)
3. Hao Wang (Nanyang Technological University)
4. Gao Cong (Nanyang Technological University)
5. Zhifeng Bao (Royal Melbourne Institute of Technology)

BibTeX Citation

@inproceedings{mo_sigmod23,
        title = {{Lemo: A Cache-Enhanced Learned Optimizer for Concurrent Queries}},
        author = {Mo, Songsong and Chen, Yile and Wang, Hao and Cong, Gao and Bao, Zhifeng},
        series = {{SIGMOD} '23},
        booktitle = {Proceedings of the {ACM} {SIGMOD} International Conference on Management of Data},
        publisher = {Association for Computing Machinery},
        doi = {10.1145/3626734},
        url = {https://dl.acm.org/doi/10.1145/3626734},
        year = {2023}
}

Incoming Citations (Sorted by Pagerank)

Showing 13 of 13 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
7,546	Learned Offline Query Planning via Bayesian Optimization	2025	SIGMOD	5.4966669e-05
8,638	LIMAO: A Framework for Lifelong Modular Learned Query Optimization	2025	VLDB	5.2965922e-05
9,229	Finding Missed Optimizations in DBMSs through Unbalanced Short-Circuit Query Construction	2026	SIGMOD	5.2032182e-05
9,556	Athena: An Effective Learning-based Framework for Query Optimizer Performance Improvement	2025	SIGMOD	5.1580326e-05
10,135	Optimizing Time Series Queries with Versions	2024	SIGMOD	5.0727027e-05
10,343	An Elephant Under The Microscope: Analyzing The Interaction Of Optimizer Components In PostgreSQL	2025	SIGMOD	5.0176429e-05
10,418	AgenticScholar: Agentic Data Management with Pipeline Orchestration for Scholarly Corpora	2026	SIGMOD	4.9769913e-05
10,495	NeurBench: A Benchmark Suite for Learned Database Components with Drift Modeling: [Experiments & Analysis]	2026	SIGMOD	4.9769913e-05
10,607	SEFRQO: A Self-Evolving Fine-Tuned RAG-Based Query Optimizer	2026	SIGMOD	4.9769913e-05
10,933	TATA: An Efficient Framework for Task Transfer in Query Plan Representation	2026	VLDB	4.9769913e-05
10,947	Towards Industrial-Scale Parametric Query Optimization	2026	VLDB	4.9769913e-05
11,295	AQETuner: Reliable Query-level Configuration Tuning for Analytical Query Engines	2025	VLDB	4.9769913e-05
11,459	RankPQO: Learning-to-Rank for Parametric Query Optimization	2025	VLDB	4.9769913e-05

Outgoing Citations (Sorted by Pagerank)

Showing 20 of 20 cited papers.

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

Rank	Cited Paper	Year	Venue	Pagerank
15	How Good Are Query Optimizers, Really?	2016	VLDB	0.00061067652
129	Efficient and Extensible Algorithms for Multi Query Optimization	2000	SIGMOD	0.00030395767
144	Neo: A Learned Query Optimizer	2019	VLDB	0.00029090793
200	Continuously Adaptive Continuous Queries over Streams	2002	SIGMOD	0.00025444144
361	Bao: Making Learned Query Optimization Practical	2021	SIGMOD	0.00020000855
390	QPipe: A Simultaneously Pipelined Relational Query Engine	2005	SIGMOD	0.00019265472
669	SharedDB: Killing One Thousand Queries With One Stone	2012	VLDB	0.00014975391
831	Pipelining in Multi-Query Optimization	2001	PODS	0.00013583882
1,034	A Scalable, Predictable Join Operator for Highly Concurrent Data Warehouses	2009	VLDB	0.00012389548
1,040	The DataPath System: A Data-Centric Analytic Processing Engine for Large Data Warehouses	2010	SIGMOD	0.00012358804
1,132	Efficient Exploitation of Similar Subexpressions for Query Processing	2007	SIGMOD	0.00011893781
1,195	Balsa: Learning a Query Optimizer Without Expert Demonstrations	2022	SIGMOD	0.00011574218
2,209	Lero: A Learning-to-Rank Query Optimizer	2023	VLDB	8.8360101e-05
2,225	Shared Workload Optimization	2014	VLDB	8.8062552e-05
2,248	QueryFormer: A Tree Transformer Model for Query Plan Representation	2022	VLDB	8.7567205e-05
2,686	Cost-based or Learning-based? A Hybrid Query Optimizer for Query Plan Selection	2022	VLDB	8.1300913e-05
2,837	Query Performance Prediction for Concurrent Queries using Graph Embedding	2020	VLDB	7.9495917e-05
4,057	The Case for Precision Sharing	2004	VLDB	6.8230987e-05
4,732	MQJoin: Efficient Shared Execution of Main-Memory Joins	2016	VLDB	6.4439712e-05
7,344	Scalable Multi-Query Execution using Reinforcement Learning	2021	SIGMOD	5.5455974e-05

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