ERD and Keys A hotel has many rooms.  A guest can make a reservation for one room or multiple rooms.  A reservation is associated with only one guest. Draw an ERD with the relationships and resolve any many to many relationships.  Create an ID for each entity you create (for example RoomID, GuestID, Reservation ID) as the Primary Key.  Identify any foreign keys in each entity where appropriate.

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A: In the intricate world of data modeling, where the digital realm mirrors the complexities of the…

Q: Explain why an index is only useful if an attribute's values change enough.

A:

Q: What is the distinction between a PRIMARY KEY and a UNIQUE constraint

A: In Step 2,   I  have  provided  distinction between a PRIMARY KEY and a UNIQUE  KEY---

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A: Question is Based on Basic Concept of Transaction management .

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A: I have answered below:

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A: Below is the relation for given EERD

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A: The answer is given below,

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A: The answer :

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Q: Why it is recommended to specify a unique index for each primary key.

A: To be determine: Why it is recommended to specify a unique index for each primary key.

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A: The answer :

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A: C   Primary Key

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Enhanced ER Model

The enhanced ER model is an abbreviation for Enhanced Entity-Relationship (EER) model. As you know, the entity-relationship (ER) model is a pictorial illustration of the relationship between various entities of a domain. In the case of a large amount of data with multiple interrelated entities, the ER diagrams become complex and tough to interpret. For such cases, the need for enhancement in the ER model was observed, and thus, the EER model was designed.