Database Systems: Design, Implementation, & Management
Database Systems: Design, Implementation, & Management
12th Edition
ISBN: 9781305627482
Author: Carlos Coronel, Steven Morris
Publisher: Cengage Learning
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Chapter 3, Problem 15P
Program Plan Intro

Primary Key:

A primary key in a database table is a field in the table that uniquely identifies every row or record present in the database table.

Example:

  • Students in Universities are assigned a unique registration number.
  • Therefore, in a STUDENT database table, the attribute “reg_no” acts as primary key.

Foreign Key:

Foreign key is a column in a relational database table which provides a relation between two tables. It provides a cross reference between tables by pointing to primary key of another table.

Example:

  • In STUDENT database table, the attribute “reg_no” acts as primary key and in COURSE database table in which the student selects his or her course, the same “reg_no” acts as foreign key for the STUDENT table.

Many to One relationship:

When more than one record in a database table is associated with only one record in another table, the relationship between the two tables is referred as many to one relationship. It is also represented as M: 1 relationship.

One to Many relationships:

When one record in a database table is associated with more than one record in another table, the relationship between the two tables is referred as one to many relationships. It is also represented as1: M relationship. This is the opposite of many to one relationship.

CROW FOOT ERD:

The Crow Foot ERD is an Entity Relationship Diagram which is used to represent the cardinalities present in the basic ER diagram. It is used to represent the relationships present between two tuples or tables present in the database.

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Chapter 3 Solutions

Database Systems: Design, Implementation, & Management

Ch. 3 - Prob. 11RQCh. 3 - Prob. 12RQCh. 3 - Use Figure Q3.13 to answer Questions 1317. FIGURE...Ch. 3 - Create the table that results from applying a...Ch. 3 - Write the relational algebra formula to apply an...Ch. 3 - Create the table that results from applying an...Ch. 3 - Using the tables in Figure Q3.13, create the table...Ch. 3 - Prob. 18RQCh. 3 - Prob. 19RQCh. 3 - Prob. 20RQCh. 3 - Identify and describe the components of the table...Ch. 3 - Identify the primary keys. FIGURE Q3.22 THE...Ch. 3 - Identify the foreign keys. FIGURE Q3.22 THE...Ch. 3 - Create the ERM. FIGURE Q3.22 THE CH03_THEATER...Ch. 3 - Create the relational diagram to show the...Ch. 3 - Prob. 26RQCh. 3 - What would be the conceptual view of the INDEX...Ch. 3 - Prob. 1PCh. 3 - Prob. 2PCh. 3 - Do the tables exhibit referential integrity?...Ch. 3 - Describe the type(s) of relationship(s) between...Ch. 3 - Prob. 5PCh. 3 - Prob. 6PCh. 3 - Prob. 7PCh. 3 - Prob. 8PCh. 3 - Create the relational diagram to show the...Ch. 3 - Prob. 10PCh. 3 - Prob. 11PCh. 3 - Create the relational diagram to show the...Ch. 3 - Prob. 13PCh. 3 - Do the tables exhibit referential integrity?...Ch. 3 - Prob. 15PCh. 3 - Prob. 16PCh. 3 - For each table, identify the primary key and the...Ch. 3 - Prob. 18PCh. 3 - Do the tables exhibit referential integrity?...Ch. 3 - Identify the TRUCK tables candidate key(s). FIGURE...Ch. 3 - For each table, identify a superkey and a...Ch. 3 - Prob. 22PCh. 3 - Prob. 23PCh. 3 - Prob. 24PCh. 3 - Create the ERD. (Hint: Look at the table contents....Ch. 3 - Prob. 26PCh. 3 - Prob. 27PCh. 3 - Prob. 28PCh. 3 - Create the table that would result from applying...Ch. 3 - Create the table that would result from applying...Ch. 3 - Create the table that would result from applying a...
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