Error-Correcting Keys in Relational Databases

نویسندگان

  • János Demetrovics
  • Gyula O. H. Katona
  • Dezsö Miklós
چکیده

Suppose that the entries of a relational database are collected in an unreliable way, that is the actual database may differ from the true database in at most one data of each individual. An error-correcting key is such a set of attributes, that the knowledge of the actual data of an individual in this set of attributes uniquely determines the individual. It is showed that if the minimal keys are of size at most k, then the smallest sizes of the minimal error-correcting keys can be ck and this is the best possible, all minimal error-correcting keys have size at most 3k.

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تاریخ انتشار 2000