Free Join: Unifying Worst-Case Optimal and Traditional Joins

Summary: Free Join unifies WCOJ and traditional binary joins, using WCOJ for cyclic parts and binary plans for acyclic parts. A unifying plan, a hash+trie data structure, and Rust optimizations let the system match or beat both baselines on benchmarks. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: 6654
Venue: SIGMOD
Year: 2023
Pagerank: 5.1202075e-05
Overall Rank: 6,294 | 56.26%
DOI: 10.1145/3589295

Incoming Non-self Citations Over Time

Authors

Incoming Citations (Sorted by Pagerank)

Showing 9 of 9 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
4,466	Robust Join Processing with Diamond Hardened Joins	2024	VLDB	6.1545841e-05
5,772	Predicate Transfer: Efficient Pre-Filtering on Multi-Join Queries	2024	CIDR	5.3313794e-05
7,122	Debunking the Myth of Join Ordering: Toward Robust SQL Analytics	2025	SIGMOD	4.8199209e-05
9,034	Extending SQL to Return a Subdatabase	2025	SIGMOD	4.3997447e-05
10,296	FlowLog: Efficient and Extensible Datalog via Incrementality	2026	VLDB	4.1905499e-05
10,498	HoneyComb: A Parallel Worst-Case Optimal Join on Multicores	2025	SIGMOD	4.1905499e-05
10,523	cuMatch: A GPU-based Memory-Efficient Worst-case Optimal Join Processing Method for Subgraph Queries with Complex Patterns	2025	SIGMOD	4.1905499e-05
10,740	Subgraph Matching: A New Decomposition Based Approach	2025	VLDB	4.1905499e-05
10,997	Towards a Converged Relational-Graph Optimization Framework	2024	SIGMOD	4.1905499e-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	0.0040465394
59	Efficiently Compiling Efficient Query Plans for Modern Hardware	2011	VLDB	0.0006445664
71	How Good Are Query Optimizers, Really?	2016	VLDB	0.00059446482
116	Eddies: Continuously Adaptive Query Processing	2000	SIGMOD	0.00046191288
341	EmptyHeaded: A Relational Engine for Graph Processing	2016	SIGMOD	0.00026850764
407	Database Cracking	2007	CIDR	0.00023941779
503	Worst-case Optimal Join Algorithms	2012	PODS	0.00021517145
848	Everything You Always Wanted to Know About Compiled and Vectorized Queries But Were Afraid to Ask	2018	VLDB	0.00015933538
1,334	Optimizing Subgraph Queries by Combining Binary and Worst-Case Optimal Joins	2019	VLDB	0.00012543633
1,452	What do Shannon-type Inequalities, Submodular Width, and Disjunctive Datalog have to do with one another?	2017	PODS	0.00011922523
1,902	Hash joins and hash teams in Microsoft SQL Server	1998	VLDB	0.0001015225
2,281	Adopting Worst-Case Optimal Joins in Relational Database Systems	2020	VLDB	9.122455e-05
2,445	Data Management for Data Science: Towards Embedded Analytics	2020	CIDR	8.7999299e-05
2,962	Kuzu* Graph Database Management System	2023	CIDR	7.8069285e-05
3,897	Updating a Cracked Database	2007	SIGMOD	6.6526754e-05
5,329	Generalized Hash Teams for Join and Group-by	1999	VLDB	5.5652298e-05

Semantically Similar Papers

Overall Rank	Paper	Year	Venue	Pagerank
1,621	Adaptive Optimization of Very Large Join Queries	2018	SIGMOD	0.00011105663
11,898	Let's Rethink Join Optimization in Distributed Systems	2015	CIDR	4.1905499e-05
1,334	Optimizing Subgraph Queries by Combining Binary and Worst-Case Optimal Joins	2019	VLDB	0.00012543633
4,430	Towards a Worst-Case I/O-Optimal Algorithm for Acyclic Joins	2016	PODS	6.1879319e-05
2,298	Joins via Geometric Resolutions: Worst-case and Beyond	2015	PODS	9.0746479e-05
503	Worst-case Optimal Join Algorithms	2012	PODS	0.00021517145
4,466	Robust Join Processing with Diamond Hardened Joins	2024	VLDB	6.1545841e-05
6,647	Fast Join Project Query Evaluation using Matrix Multiplication	2020	SIGMOD	4.9729424e-05
3,519	Scalable Computation of Acyclic Joins (Extended Abstract)	2006	PODS	7.0181381e-05
2,281	Adopting Worst-Case Optimal Joins in Relational Database Systems	2020	VLDB	9.122455e-05