The cardinality of the number of rows in the relation. The number in C ranges from the number in A times the number in B all the way to 0.
The cardinality of the number of rows in the relation. The number in C ranges from the number in A times the number in B all the way to 0.
The arity is the number of columns in the relation. In relational algebra, all columns of the relations are kept, and thus the arity of C is the arity of A plus B. The arity of both A and B must be greater than one.
The arity is the number of columns in the relation. In relational algebra, all columns of the relations are kept, and thus the arity of C is the arity of A plus B. The arity of both A and B must be greater than one.
The cardinality of the number of rows in the relation. The number in C ranges from the number in A times the number in B all the way to 0. The arity is the number of columns in the relation. In relational algebra, all columns of the relations are kept, and thus the arity of C is the arity of A plus B. The arity of both A and B must be greater than one.
Relation C is the join of relation A and relation B on condition p. Which of the following statements must be true in all cases?
- The cardinality of C is greater than the cardinality of A
- The cardinality of C is less than the cardinality of A
- The arity of C is greater than the arity of A
- The arity of C is less than the arity of A
- None of the above
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