Database Systems: Design, Implementation, & Management
11th Edition
ISBN: 9781285196145
Author: Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel
Publisher: Cengage Learning
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Chapter 5, Problem 11RQ
Program Plan Intro
Primary key (PK):
- To identify each record in a table, at least there must be one data field, which should be unique.
- That is corresponding data field of every record should be unique.
- It is called primary key.
- Primary key is used to identify the unique record from a collection of records.
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Chapter 5 Solutions
Database Systems: Design, Implementation, & Management
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- Briefly explain change models.arrow_forwardWhat issues may emerge as a result of vertical partitioning a relationship and the underlying factors that influence them.arrow_forwardExplain the advantages and disadvantages of each model, as well as the step(s) that you feel should be added or deleted to improve the effectiveness of each model.arrow_forward
- What are the deficiencies to using group policyarrow_forwardIf one characteristic may have several values, how does it differ from a recurring group?arrow_forwardIf you have an entity with 100 different attributes, what would be some strategies to model this entity? What are some questions you would want to know about the individual attributes?arrow_forward
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- What issues may emerge as a result of vertical partitioning of a relationship, as well as the general circumstances that can influence them, are discussed.arrow_forwardWrite down the various types of characteristics in the Entity-Relationship (ER) model.arrow_forwardUse the ER Diagram shown on Figure 1 to answer question 9: 9. According to the ER diagram on Figure 1, which of the following is true? A) For each employee, we will keep track of either the employee name or the unique employee ID. B) For each department, we will keep track of either the unique department ID or the department location. C) Each employee reports to exactly one department. A department may have many employees reporting to it, but it does not have to have any. D) None of the above. Answer: EmpID EmpName EMPLOYEE Reports To Figure 1 DeptID DeptLocation DEPARTMENTarrow_forward
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