Representing minimum cardinality in a physical database design can be tricky depending on whether the parent-child relationship is O-O, M-O, O-M, or M-M. Give an example of one of these minimum cardinalities and how it would affect the physical database design. What are referential integrity actions, and how could you use them in your example?
Cardinality and Referential Integrity:
Cardinality, or degree of relationship, refers to the uniqueness of data values in a column, or in other words, it represents a relationship between the row of one table to the row of other. The referential integrity property says that each value of an attribute in table A must exist as a value of an attribute in Table B (foreign key).
Answer and Explanation:
Cardinality defines the uniqueness of the data. High or maximum cardinality means the attribute has more unique values. For example, Roll No....
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fromChapter 9 / Lesson 4
Get to know the different models of database management systems and learn how each one is used to systematically organize large amounts of data in a logical manner.