Database Design (Other (Not Listed) Sample)

Name:
Professor’s name
Subject
Date:
Database Design
14. Create a Crow’s Foot ERD to include the following business rules for the Prod Co Company:
ERD for Prod Co Company
15. Write rule from ERD given.
¯ Each publisher submits many contracts
¯ Each contact is submitted by only one publisher
¯ A publisher publishes many books
¯ Each book is published by only one publisher
¯ An author signs many contracts
¯ Each contract is signed by only one author
¯ An author writes many books
¯ Each book is written by only one author.
17. Primary key and foreign key
* TRUCK Table:
¯ Primary key: TRUCK_NUM
¯ Foreign key: BASE_CODE, TYPE_CODE
* TRUCK Table:
¯ Primary key: BASE_CODE
¯ Foreign key: None
* TYPE Table:
¯ Primary key: TYPE_CODE
¯ Foreign key: None
18. Entity integrity
Yes, the primary keys in all tables are not NULL.
19. Referential Integrity.
Yes, TRUCK table has two foreign key; BASE_CODE and TYPE_CODE, which refer to TRUCK and TYPE table respectively. One cannot delete any record in the two tables (TRUCK and TYPE) without first deleting the record in the TRUCK table; this avoids TRUCK table referring to NULL record in the other two tables.
20. Candidate key in TRUCK table;
* TRUCK_SERIAL_NUM
* TRUCK_NUM