Entity Relationship Questions

1. What word describes the relationship that exists between two (or more) entities such as one-to-one, one-to-many, many-to-one, many-to-many?

  • Optionality
  • Entity
  • Attribute
  • Cardinality

2. What word describes the nature of the relationship i.e. whether it is optional or mandatory?

  • Cardinality
  • Entity occurrence
  • Optionality
  • Determinant

3. Look at the diagram below then answer the following questions:


4. Which one of the following do the boxes in the diagram represent?

  • Attributes
  • Entities
  • Relationships
  • primary Key

5. Which one of the following do the lines in the diagram represent?

  • Attributes
  • Entities
  • Relationships
  • primary Key

6. What is the nature of the relationship between D and C?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

7. What is the nature of the relationship between A and D?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

8. What is the nature of the relationship between B and C?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

9. What is the nature of the relationship between A and B?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

10. What type of relationship exists between A and B?

  • Optional to Mandatory
  • Mandatory to Optional
  • Optional to Optional
  • Mandatory to Mandatory

11. What type of relationship exists between A and D?

  • Optional to Mandatory
  • Mandatory to Optional
  • Optional to Optional
  • Mandatory to Mandatory

12. What do A, B, C and D represent in the diagram?

  • Attribute descriptions
  • Entity names
  • Entity occurrences

13. Which of the following relationships are not acceptable in completed ER Diagrams?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

14. A college has five teachers. Each teacher takes about three classes a day. What is the relationship between teachers and their classes?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

15. There are many students in each class and students have several classes a day. What is the relationship between students and classes?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

16. The college keeps a personal record of each student in the college. Which one of the following describes the relationship between each college personal record and its students?

  • One to One
  • One to Many
  • Many to One
  • Many to Many

17. Below is a table, which represents a Entity and its occurrences. Look at it closely then answer the following questions:
CUSTOMER

Customer_No / Surname / First_Name / Telephone_No
123 / Grove / Olive / 01783 023999
125 / Jenkins / Phyllis / 01785 233242
130 / Jelly / Kelly / 01270 345566
234 / Sumner / Gerald / 01260 232322

18. What does the data highlighted by the grey line represent in the diagram?

  • A attribute
  • A record
  • A primary key
  • A field

19. What is signified by the column marked Surname?

  • A record
  • A primary key
  • An attribute
  • An entity

20. What does the box containing 0125 represent on the second row of the table?

  • A record
  • A primary key
  • An attribute occurrence
  • An entity

21. What does the underline on Customer_No represent?

  • a record
  • A primary key
  • An attribute
  • An entity

22. What type of fields/attributes would we apply an index to in the table?

  • Primary key
  • Surname
  • First Name
  • Telephone No

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