Relaxed Currency and Consistency: How to Say "Good Enough" in SQL

Summary: Proposes explicit C&C (currency and consistency) constraints in SQL to express 'good enough' data across asynchronous replicas. MTCache prototype enforces C&C at compile-time and validates currency at runtime with dynamic plans, integrated into the optimizer to guarantee data sufficiency. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: hfc7a10402f9e4edc
Venue: SIGMOD
Year: 2004
Pagerank: 7.9678605e-05
Overall Rank: 2,826 | 81.01%
DOI: 10.1145/1007568.1007661

Incoming Non-self Citations Over Time

Authors

1. Hongfei Guo (University of Wisconsin)
2. Per-Åke Larson (Microsoft)
3. Raghu Ramakrishnan (University of Wisconsin)
4. Jonathan Goldstein (Microsoft)

BibTeX Citation

@inproceedings{guo_sigmod04,
        title = {{Relaxed Currency and Consistency: How to Say "Good Enough" in SQL}},
        author = {Guo, Hongfei and Larson, Per-Åke and Ramakrishnan, Raghu and Goldstein, Jonathan},
        series = {{SIGMOD} '04},
        booktitle = {Proceedings of the {ACM} {SIGMOD} International Conference on Management of Data},
        publisher = {Association for Computing Machinery},
        doi = {10.1145/1007568.1007661},
        url = {https://dl.acm.org/doi/10.1145/1007568.1007661},
        year = {2004}
}

Incoming Citations (Sorted by Pagerank)

Showing 10 of 10 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
775	Lazy Database Replication with Snapshot Isolation	2006	VLDB	0.00014081697
1,447	Consistency Rationing in the Cloud: Pay only when it matters	2009	VLDB	0.00010627871
3,616	Caching with "Good Enough" Currency, Consistency, and Completeness	2005	VLDB	7.1585227e-05
5,699	Relaxed Currency Serializability for Middle-Tier Caching and Replication	2006	SIGMOD	6.0317805e-05
5,806	Fine-Grained Replication and Scheduling with Freshness and Correctness Guarantees	2005	VLDB	5.988633e-05
6,349	Robust Set Reconciliation	2014	SIGMOD	5.8092399e-05
8,013	Support for Relaxed Currency and Consistency Constraints in MTCache	2004	SIGMOD	5.407108e-05
11,844	Confidence Bounded Replica Currency Estimation	2022	SIGMOD	4.9793485e-05
12,921	Data Currency in Replicated DHTs	2007	SIGMOD	4.9793485e-05
13,000	TRAC: Toward Recency and Consistency Reporting in a Database with Distributed Data Sources	2006	VLDB	4.9793485e-05

Outgoing Citations (Sorted by Pagerank)

Showing 14 of 14 cited papers.

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

Rank	Cited Paper	Year	Venue	Pagerank
553	Optimizing Queries Using Materialized Views: A Practical, Scalable Solution	2001	SIGMOD	0.0001652591
659	Adaptive Precision Setting for Cached Approximate Values	2001	SIGMOD	0.00015015728
1,122	Least Expected Cost Query Optimization: An Exercise in Utility	1999	PODS	0.0001193884
1,669	Replica Control in Distributed Systems: An Asynchronous Approach	1991	SIGMOD	9.9330676e-05
1,755	Offering a Precision-Performance Tradeoff for Aggregation Queries over Replicated Data	2000	VLDB	9.7206727e-05
2,181	Probabilistic Optimization of Top N Queries	1999	VLDB	8.9082736e-05
2,271	Transparent Mid-Tier Database Caching in SQL Server	2003	SIGMOD	8.7123265e-05
2,489	FAS - a Freshness-Sensitive Coordination Middleware for a Cluster of OLAP Components	2002	VLDB	8.3968758e-05
2,724	Efficient Numerical Error Bounding for Replicated Network Services	2000	VLDB	8.0923863e-05
2,890	Improving Performance in Replicated Databases through Relaxed Coherency	1995	VLDB	7.9045441e-05
3,345	Cache Tables: Paving the Way for an Adaptive Database Cache	2003	VLDB	7.3949085e-05
4,689	DBCache: Middle-tier Database Caching for Highly Scalable e-Business Architectures	2003	SIGMOD	6.4690629e-05
6,928	Balancing Performance and Data Freshness in Web Database Servers	2003	VLDB	5.6414724e-05
6,929	Using Latency-Recency Profiles for Data Delivery on the Web	2002	VLDB	5.6414724e-05

Semantically Similar Papers

#	Overall Rank	Paper	Year	Venue
1	595	ConQuer: Efficient Management of Inconsistent Databases	2005	SIGMOD
2	1,238	Cache Consistency and Concurrency Control in a Client/Server DBMS Architecture	1991	SIGMOD
3	9,617	MCC-DB: Minimizing Cache Conflicts in Multi-core Processors for Databases	2009	VLDB
4	2,430	Data Caching Tradeoffs in Client-Server DBMS Architectures	1991	SIGMOD
5	11,844	Confidence Bounded Replica Currency Estimation	2022	SIGMOD
6	13,231	An Asynchronous Avoidance-Based Cache Consistency Algorithm for Client Caching DBMSs	1998	VLDB
7	5,281	Determining the Currency of Data	2011	PODS
8	5,699	Relaxed Currency Serializability for Middle-Tier Caching and Replication	2006	SIGMOD
9	3,616	Caching with "Good Enough" Currency, Consistency, and Completeness	2005	VLDB
10	8,013	Support for Relaxed Currency and Consistency Constraints in MTCache	2004	SIGMOD