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Boolean conjunctive query

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In the theory of relational databases, a Boolean conjunctive query is a query in the form , where each is a relation symbol and each is a tuple of variables and constants; the number of elements in is equal to the arity of . Such a query evaluates to either true or false depending on whether the relations in the database contains the appropriate tuples of values.

References

  • G. Gottlob, N. Leone, F. Scarcello (2001). "The complexity of acyclic conjunctive queries". Journal of the ACM (JACM). 48 (3): 431–498. doi:10.1145/382780.382783. {{cite journal}}: Cite has empty unknown parameter: |1= (help)CS1 maint: multiple names: authors list (link)