This topic contains a solution. Click here to go to the answer

Author Question: Describe and give an example of generalization and specialization. What will be an ideal ... (Read 20 times)

Ebrown

  • Hero Member
  • *****
  • Posts: 567
Describe and give an example of generalization and specialization.
 
  What will be an ideal response?

Question 2

What does integrity mean in the context of data management?
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

makaylafy

  • Sr. Member
  • ****
  • Posts: 347
Answer to Question 1

Generalization is a relationship in which one class is the more abstract expression of the properties of a set of classes: a Tree class embodies properties common to Oak, Birch, and Cedar classes. Conversely, specialization is a relationship in which a class is the less abstract expression of another class: a Rose is a Flower but the Flower class does not express the specific features of a Rose that sets it apart from other flowers. The result of generalization is a superclass (or a parent), while specialization arrives as subclasses (or children).

Answer to Question 2

A relational DBMS protects data integrity at four levels: column (or attribute), row (or entity), inter-table, and procedural.
 Attribute integrity is ensured by type definition, foreign keys, and constraints.
 Entity integrity is assured by the primary key: one, and only one, entity within a table can be identified by a specific value (or combination of values) in the primary key.
 Inter-table integrity is called referential integrity and is implemented by enforcing the constraints of foreign keys.
 Procedural integrity is used when the relationships among entities are too complex for the other mechanisms. The main tools of procedural integrity are triggers, stored procedures, and transaction processing.





 

Did you know?

Approximately 500,000 babies are born each year in the United States to teenage mothers.

Did you know?

Hyperthyroidism leads to an increased rate of metabolism and affects about 1% of women but only 0.1% of men. For most people, this increased metabolic rate causes the thyroid gland to become enlarged (known as a goiter).

Did you know?

Pink eye is a term that refers to conjunctivitis, which is inflammation of the thin, clear membrane (conjunctiva) over the white part of the eye (sclera). It may be triggered by a virus, bacteria, or foreign body in the eye. Antibiotic eye drops alleviate bacterial conjunctivitis, and antihistamine allergy pills or eye drops help control allergic conjunctivitis symptoms.

Did you know?

More than 30% of American adults, and about 12% of children utilize health care approaches that were developed outside of conventional medicine.

Did you know?

Immunoglobulin injections may give short-term protection against, or reduce severity of certain diseases. They help people who have an inherited problem making their own antibodies, or those who are having certain types of cancer treatments.

For a complete list of videos, visit our video library