Chapter 4 Database Management The entity relationship model (ERM) is dependent on the database type - correct answer ✔✔False The Crow's Foot notation is less implementation oriented than the Chen notation - correct answer ✔✔False An entity in the entity-relationship model corresponds to a table in the relational environment - correct answer ✔✔True In the entity relationship model, a table row corresponds to an entity instance - correct answer ✔✔True In the Chen and Crow's Foot notations, an entity is represented with a rectangle containing the entity's name - correct answer ✔✔True In the original Chen notation, each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line - correct answer ✔✔True Software vendors have adopted the Chen representation because of its compact representation - correct answer ✔✔False A composite identifier is a primary key composed of more than one attribute - correct answer ✔✔True The Crow's Foot notation easily identifies multivalued attributes - correct answer ✔✔False Composite attributes make it easier to facilitate detailed queries - correct answer ✔✔False Connectivities and cardinalities are established by concise statements known as business rules - correct answer ✔✔True 1 / 2
In Chen notation, there is no way to represent cardinality - correct answer ✔✔False In implementation terms, an entity is existence-dependent if it has a mandatory primary key - correct answer ✔✔False A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity - correct answer ✔✔False A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship - correct answer ✔✔True In a 1:M relationship, to avoid the possibility of referential integrity errors, the data of the "1" side must be loaded first - correct answer ✔✔True Relationships between entities always operate in one direction - correct answer ✔✔False The existence of a mandatory relationship indicates that the minimum cardinality is 0 or 1 for the mandatory entity - correct answer ✔✔False Unary relationships are common in manufacturing industries - correct answer ✔✔True Referential integrity and participation are both bidirectional, meaning that they must be addressed in both directions along a relationship - correct answer ✔✔False To implement a small database, a database designer must know the "1" and the "M" sides of each relationship and whether the relationships are mandatory or optional - correct answer ✔✔True The process of database design is a sequential process - correct answer ✔✔False The entity relationship diagram (ERD) represents the _____ database as viewed by the end user - correct answer ✔✔d. conceptual
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