A LESS COSTLY CONSTBAIhTS CHECKING FUR JOIN DEPChDEKY
نویسنده
چکیده
A set of n tuples in a relation of a relational database design is tested tlpon the constraints of the join dependency. Some constraint equalities are found to be redundant. To remove thfs superEluity, the universe of atttbutes is partitioned into n dfsjolnt sets and a new notat.ion of join dependency is introduced. The checking time In each run of n tuples is significantly reduced by a factor of (n-1)/2 when n > 3. The result of less costly constraints checktng is of great importance for a large number of tuples in a relation.
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