Balsa: Learning a Query Optimizer Without Expert Demonstrations

Summary: Balsa uses deep RL to learn a query optimizer without expert demonstrations, from a simple simulator to safe real-execution fine-tuning. On Join Order Benchmark, it matches two expert optimizers after ~2 hours and beats them up to 2.8x with training. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: hc15b634968a29395
Venue: SIGMOD
Year: 2022
Pagerank: 0.00011563985
Overall Rank: 1,199 | 91.95%
DOI: 10.1145/3514221.3517885

Incoming Non-self Citations Over Time

Authors

1. Zongheng Yang (University of California Berkeley)
2. Wei-Lin Chiang (University of California Berkeley)
3. Sifei Luan (University of California Berkeley)
4. Gautam Mittal (University of California Berkeley)
5. Michael Luo (University of California Berkeley)
6. Ion Stoica (University of California Berkeley)

BibTeX Citation

@inproceedings{yang_sigmod22,
        title = {{Balsa: Learning a Query Optimizer Without Expert Demonstrations}},
        author = {Yang, Zongheng and Chiang, Wei-Lin and Luan, Sifei and Mittal, Gautam and Luo, Michael and Stoica, Ion},
        series = {{SIGMOD} '22},
        booktitle = {Proceedings of the {ACM} {SIGMOD} International Conference on Management of Data},
        publisher = {Association for Computing Machinery},
        doi = {10.1145/3514221.3517885},
        url = {https://dl.acm.org/doi/10.1145/3514221.3517885},
        year = {2022}
}

Incoming Citations (Sorted by Pagerank)

Showing 9 of 59 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
10,741	OBELISK: Efficient Offline Query Planning with Bayesian Optimization-Informed Language Model Reasoning	2026	VLDB	4.9793485e-05
10,751	Toward Drift-Aware Database Benchmarking	2026	VLDB	4.9793485e-05
10,883	QDBO: A Real-time Quantum-augmented Database System Optimizer	2026	VLDB	4.9793485e-05
10,924	TATA: An Efficient Framework for Task Transfer in Query Plan Representation	2026	VLDB	4.9793485e-05
10,938	Towards Industrial-Scale Parametric Query Optimization	2026	VLDB	4.9793485e-05
11,283	Robust Plan Evaluation based on Approximate Probabilistic Machine Learning	2025	VLDB	4.9793485e-05
11,425	Learned Cost Models for Query Optimization: From Batch to Streaming Systems	2025	VLDB	4.9793485e-05
11,443	LEAP: A Low-cost Spark SQL Query Optimizer using Pairwise Comparison	2025	VLDB	4.9793485e-05
11,453	RankPQO: Learning-to-Rank for Parametric Query Optimization	2025	VLDB	4.9793485e-05

Outgoing Citations (Sorted by Pagerank)

Showing 16 of 16 cited papers.

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

Rank	Cited Paper	Year	Venue	Pagerank
1	Access Path Selection in a Relational Database Management System	1979	SIGMOD	0.0023947656
15	How Good Are Query Optimizers, Really?	2016	VLDB	0.00061066921
85	Learned Cardinalities: Estimating Correlated Joins with Deep Learning	2019	CIDR	0.00035864347
145	Neo: A Learned Query Optimizer	2019	VLDB	0.0002908188
318	DeepDB: Learn from Data, not from Queries!	2020	VLDB	0.00021167555
362	Bao: Making Learned Query Optimization Practical	2021	SIGMOD	0.00019989474
406	Deep Unsupervised Cardinality Estimation	2020	VLDB	0.00019045544
461	An End-to-End Learning-based Cost Estimator	2020	VLDB	0.00017829982
512	NeuroCard: One Cardinality Estimator for All Tables	2021	VLDB	0.00017050173
692	Selectivity Estimation for Range Predicates using Lightweight Models	2019	VLDB	0.00014741011
1,064	Are We Ready For Learned Cardinality Estimation?	2021	VLDB	0.00012202282
1,369	Towards Scalable Dataframe Systems	2020	VLDB	0.00010899832
1,433	Towards a Learning Optimizer for Shared Clouds	2019	VLDB	0.00010677711
1,603	SkinnerDB: Regret-Bounded Query Evaluation via Reinforcement Learning	2019	SIGMOD	0.00010097649
2,478	Learning a Partitioning Advisor for Cloud Databases	2020	SIGMOD	8.4079121e-05
3,562	Astrid: Accurate Selectivity Estimation for String Predicates using Deep Learning	2021	VLDB	7.2046519e-05

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