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 92 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?

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.

Did you know?

In 1885, the Lloyd Manufacturing Company of Albany, New York, promoted and sold "Cocaine Toothache Drops" at 15 cents per bottle! In 1914, the Harrison Narcotic Act brought the sale and distribution of this drug under federal control.

Did you know?

Signs and symptoms that may signify an eye tumor include general blurred vision, bulging eye(s), double vision, a sensation of a foreign body in the eye(s), iris defects, limited ability to move the eyelid(s), limited ability to move the eye(s), pain or discomfort in or around the eyes or eyelids, red or pink eyes, white or cloud spots on the eye(s), colored spots on the eyelid(s), swelling around the eyes, swollen eyelid(s), and general vision loss.

Did you know?

Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.

Did you know?

The most common childhood diseases include croup, chickenpox, ear infections, flu, pneumonia, ringworm, respiratory syncytial virus, scabies, head lice, and asthma.

For a complete list of videos, visit our video library