Although a large number of queries have cardinality constraints, database engines have minimal support for cardinality assurance. Inability to meet cardinality constraints requires a user to undertake a cumbersome trial-and-error refinement process. A possible solution to this problem is query relaxation. However, attaining exact query cardinality is a NP-Hard problem. In this work we present QRelX, a novel algorithm for cardinality assurance that relaxes queries efficiently while minimizing relaxation of result queries. For this purpose, QRelX uses a combination of query space transformation, layer-based traversal and incremental cardinality estimation. Preliminary experiments indicate that QRelX is more efficient than traditional algorithms and it successfully minimizes relaxation.

• This report represents the work of one or more WPI undergraduate students submitted to the faculty as evidence of completion of a degree requirement. WPI routinely publishes these reports on its website without editorial or peer review.

Creator

• Vartak, Manasi Pradeep

Publisher

• Worcester Polytechnic Institute

Identifier

• E-project-102709-144741

Advisor

• Rundensteiner, Elke A.

Year

• 2009

Date created

• 2009-10-27

Resource type

• Major Qualifying Project

Major

• Computer Science

Rights statement

• In Copyright

Last modified

• 2020-12-31