CORDS: Automatic Generation of Correlation Statistics in DB2

Summary: CORDS automatically discovers correlations and soft FDs between columns to improve DB2 query optimization. Scalable discovery, visual graph outputs, and ranking by impact; yields targeted statistics that speed plans by orders of magnitude. (summarized by gpt-5-nano on Feb 09 2026)

Paper ID: 9291
Venue: VLDB
Year: 2004
Pagerank: 5.5073838e-05
Overall Rank: 8,012 | 45.04%
DOI: 10.1016/B978-012088469-8.50142-X

Incoming Non-self Citations Over Time

Authors

1. Ihab F. Ilyas (University of Waterloo)
2. Volker Markl (IBM)
3. Peter J. Haas (IBM)
4. Paul G. Brown (IBM)
5. Ashraf Aboulnaga (IBM)

BibTeX Citation

@article{ilyas_vldb04,
        title = {{CORDS: Automatic Generation of Correlation Statistics in DB2}},
        author = {Ilyas, Ihab F. and Markl, Volker and Haas, Peter J. and Brown, Paul G. and Aboulnaga, Ashraf},
        journal = {PVLDB},
        series = {{VLDB} '04},
        pages = {1341},
        doi = {10.1016/B978-012088469-8.50142-X},
        url = {https://doi.org/10.1016/B978-012088469-8.50142-X},
        year = {2004}
}

Incoming Citations (Sorted by Pagerank)

Showing 2 of 2 citing papers.

Rank	Citing Paper	Year	Venue	Pagerank
2,269	GORDIAN: Efficient and Scalable Discovery of Composite Keys	2006	VLDB	8.8328424e-05
6,723	Record Linkage with Uniqueness Constraints and Erroneous Values	2010	VLDB	5.792469e-05

Outgoing Citations (Sorted by Pagerank)

Showing 1 of 1 cited papers.

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

Rank	Cited Paper	Year	Venue	Pagerank
159	CORDS: Automatic Discovery of Correlations and Soft Functional Dependencies	2004	SIGMOD	0.00028129426

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