Are We Ready For Learned Cardinality Estimation?

Summary: Assess readiness of learned cardinality estimators for production; static workloads yield gains, but training/inference costs are high. Dynamic updates hurt accuracy; sensitivity to correlation, skew, and domain shifts; emphasizes cost control and trustworthiness. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: h5c05fc5e6cf8c2e5
Venue: VLDB
Year: 2021
Pagerank: 0.00012202282
Overall Rank: 1,064 | 92.85%
DOI: 10.14778/3461535.3461552

Incoming Non-self Citations Over Time

Authors

1. Xiaoying Wang (Simon Fraser University)
2. Changbo Qu (Simon Fraser University)
3. Weiyuan Wu (Simon Fraser University)
4. Jiannan Wang (Simon Fraser University)
5. Qingqing Zhou (Tencent)

BibTeX Citation

@article{wang_vldb21,
        title = {{Are We Ready For Learned Cardinality Estimation?}},
        author = {Wang, Xiaoying and Qu, Changbo and Wu, Weiyuan and Wang, Jiannan and Zhou, Qingqing},
        journal = {PVLDB},
        series = {{VLDB} '21},
        volume = {14},
        number = {9},
        pages = {1640--1654},
        doi = {10.14778/3461535.3461552},
        url = {https://doi.org/10.14778/3461535.3461552},
        year = {2021}
}

Incoming Citations (Sorted by Pagerank)

Showing 50 of 61 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
982	Cardinality Estimation in DBMS: A Comprehensive Benchmark Evaluation	2022	VLDB	0.00012714044
1,199	Balsa: Learning a Query Optimizer Without Expert Demonstrations	2022	SIGMOD	0.00011563985
1,734	Flow-Loss: Learning Cardinality Estimates That Matter	2021	VLDB	9.7545773e-05
2,004	FLAT: Fast, Lightweight and Accurate Method for Cardinality Estimation	2021	VLDB	9.2065719e-05
2,210	Lero: A Learning-to-Rank Query Optimizer	2023	VLDB	8.8257742e-05
2,342	Learned Cardinality Estimation: An In-depth Study	2022	SIGMOD	8.6060437e-05
2,522	Learned Cardinality Estimation: A Design Space Exploration and A Comparative Evaluation	2022	VLDB	8.3477168e-05
2,583	Fauce: Fast and Accurate Deep Ensembles with Uncertainty for Cardinality Estimation	2021	VLDB	8.2589758e-05
3,327	Robust Query Driven Cardinality Estimation under Changing Workloads	2023	VLDB	7.4207879e-05
3,741	FACE: A Normalizing Flow based Cardinality Estimator	2022	VLDB	7.0594076e-05
4,202	Kepler: Robust Learning for Faster Parametric Query Optimization	2023	SIGMOD	6.7374091e-05
4,311	ALECE: An Attention-based Learned Cardinality Estimator for SPJ Queries on Dynamic Workloads	2024	VLDB	6.6727978e-05
4,457	Lightweight and Accurate Cardinality Estimation by Neural Network Gaussian Process	2022	SIGMOD	6.5913732e-05
4,683	AutoSteer: Learned Query Optimization for Any SQL Database	2023	VLDB	6.4716143e-05
5,219	SafeBound: A Practical System for Generating Cardinality Bounds	2023	SIGMOD	6.222726e-05
5,456	Eraser: Eliminating Performance Regression on Learned Query Optimizer	2024	VLDB	6.1239873e-05
5,481	A Comparative Study and Component Analysis of Query Plan Representation Techniques in ML4DB Studies	2024	VLDB	6.1125124e-05
5,649	Sample-Efficient Cardinality Estimation Using Geometric Deep Learning	2024	VLDB	6.052326e-05
5,683	How Good are Learned Cost Models, Really? Insights from Query Optimization Tasks	2025	SIGMOD	6.0392183e-05
5,716	Detect, Distill and Update: Learned DB Systems Facing Out of Distribution Data	2023	SIGMOD	6.0194657e-05
5,871	PilotScope: Steering Databases with Machine Learning Drivers	2024	VLDB	5.9639223e-05
6,105	Breaking It Down: An In-depth Study of Index Advisors	2024	VLDB	5.8860941e-05
6,595	LMSFC: A Novel Multidimensional Index based on Learned Monotonic Space Filling Curves	2023	VLDB	5.7413481e-05
6,660	Speeding Up End-to-end Query Execution via Learning-based Progressive Cardinality Estimation	2023	SIGMOD	5.7178404e-05
6,791	dbET: Execution Time Distribution-based Plan Selection	2023	SIGMOD	5.6811782e-05
6,818	ASM: Harmonizing Autoregressive Model, Sampling, and Multi-dimensional Statistics Merging for Cardinality Estimation	2024	SIGMOD	5.672718e-05
7,217	Refactoring Index Tuning Process with Benefit Estimation	2024	VLDB	5.5834823e-05
7,332	Selectivity Functions of Range Queries are Learnable*	2022	SIGMOD	5.5499953e-05
7,363	PerfGuard: Deploying ML-for-Systems without Performance Regressions, Almost!	2021	VLDB	5.5418564e-05
7,429	Learning to be a Statistician: Learned Estimator for Number of Distinct Values	2022	VLDB	5.5300853e-05
7,806	Machine Learning for Cloud Data Systems: the Progress so far and the Path Forward	2021	VLDB	5.4500623e-05
7,905	CAMAL: Optimizing LSM-trees via Active Learning	2024	SIGMOD	5.4291824e-05
8,164	Efficient Query Re-optimization with Judicious Subquery Selections	2023	SIGMOD	5.3852872e-05
8,196	WISK: A Workload-aware Learned Index for Spatial Keyword Queries	2023	SIGMOD	5.3794981e-05
8,389	PARQO: Penalty-Aware Robust Plan Selection in Query Optimization	2024	VLDB	5.3413016e-05
8,659	ShadowAQP: Efficient Approximate Group-by and Join Query via Attribute-oriented Sample Size Allocation and Data Generation	2023	VLDB	5.2930951e-05
8,800	PACE: Poisoning Attacks on Learned Cardinality Estimation	2024	SIGMOD	5.2742531e-05
8,946	HAP: An Efficient Hamming Space Index Based on Augmented Pigeonhole Principle	2022	SIGMOD	5.2532874e-05
8,947	Machine Unlearning in Learned Databases: An Experimental Analysis	2024	SIGMOD	5.2532248e-05
9,020	Optimizing the cloud? Don't train models. Build oracles!	2024	CIDR	5.2355482e-05
9,113	Presto’s History-based Query Optimizer	2024	VLDB	5.2276066e-05
9,145	One Seed, Two Birds: A Unified Learned Structure for Exact and Approximate Counting	2024	SIGMOD	5.220115e-05
9,372	Efficient and Effective Cardinality Estimation for Skyline Family	2023	SIGMOD	5.1868213e-05
9,575	A Step Toward Deep Online Aggregation	2023	SIGMOD	5.1571823e-05
9,777	Understanding Robustness Issues of Updatable Learned Indexes: [Experiments & Analysis]	2026	SIGMOD	5.1314952e-05
10,103	Still Asking: How Good Are Query Optimizers, Really?	2025	VLDB	5.0789354e-05
10,184	Path-centric Cardinality Estimation for Subgraph Matching	2025	VLDB	5.0651993e-05
10,215	Color: A Framework for Applying Graph Coloring to Subgraph Cardinality Estimation	2025	VLDB	5.0584922e-05
10,216	PRICE: A Pretrained Model for Cross-Database Cardinality Estimation	2025	VLDB	5.0584922e-05
10,253	BEE: Towards Redundancy Reduction via Block-Separator Decomposition for Subgraph Matching	2026	SIGMOD	5.050482e-05

Outgoing Citations (Sorted by Pagerank)

Showing 2 of 52 cited papers.

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

Rank	Cited Paper	Year	Venue	Pagerank
4,234	Adaptive Statistics in Oracle 12c	2017	VLDB	6.7134191e-05
4,781	Learned Approximate Query Processing: Make it Light, Accurate and Fast	2021	CIDR	6.4162085e-05

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