3.1.1DefinitionofFD-pp68Section3.1.1 LetRbearelationschemeandX,YbesetsofattributesinR. AfunctionaldependencyfromXtoYexistsifandonlyif: Foreveryinstanceof|R|ofR,iftwotuplesin|R|agreeonthevaluesoftheattributesinX,thentheyagreeonthevaluesoftheattributesinY ...
data redundancy/ C6130D Document processing techniques C6160 Database management systems (DBMS)According to the analysis of existing complicated functional dependencies constraint,we conclude the conditions of defining functional dependency in XML,and then we introduce the concept of the node value ...
We describe an algorithm to test whether a multivalued dependency is implied by a set of functional and join dependencies. The worst case running time of the algorithm is O ( nm ), where n is the length of the input and m is the number of the attributes in the universe. We also ...