DATABASE FUNDAMENTALS
WHAT IS DATABASE MANAGEMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Connectivity
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Connection
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Instance
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Occurrence
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Detailed explanation-1: -The term connectivity is used to describe the relationship classification. Cardinality. expresses the maximum number of entity occurrences associated with one occurrence of the related entity. In the ERD, cardinality is indicated by placing the appropriate numbers beside the entities, using the format (x, y).
Detailed explanation-2: -There are five types of relations in the databases: one-to-one, one-to-many, many-to-one, many-to-many, and self-referencing relationships.
Detailed explanation-3: -The connectivity of a relationship describes the mapping of participating entities in the relationship. The values of connectivity are one or many. The cardinality of a relationship is the actual number of related occurrences for each of the participating entities.
Detailed explanation-4: -There are three types of relationships between the data you are likely to encounter at this stage in the design: one-to-one, one-to-many, and many-to-many.