What is the Maximum Cardinality in Database Relationship?
Based on the description given, what is the maximum cardinality between each instance of "section" and "teacher"?
A) section teacher
B) section teacher
C) section teacher
D) section teacher
Answer:
The maximum cardinality between each instance of "section" and "teacher" is C) section teacher.
In a database relationship, cardinality refers to the maximum and minimum number of instances of one entity that can be associated with a single instance of another entity. The maximum cardinality, as described in the provided data, determines the maximum number of connections or options that can be selected between two entities.
The ratio 1:n indicates the maximum possible cardinality, where 'n' signifies the maximum number of instances that can be associated with one instance of another entity. A ratio of 1:1 indicates a one-to-one relationship, while a ratio of 1:n indicates a one-to-many relationship.
It is essential to consider the minimum cardinality when defining the maximum cardinality in a database relationship. The minimum cardinality specifies the smallest number of instances of one entity that must be connected to another entity. If the minimum cardinality is greater than 0, the maximum cardinality must be equal to or greater than the minimum cardinality.
When establishing database relationships, understanding the maximum cardinality is crucial for determining the extent of connectivity between entities and ensuring data integrity. By defining the maximum cardinality accurately, database designers can create efficient and effective relationships that meet the requirements of the system.