« previous next »

Author Question: Briefly explain first, second, and third normal forms. What will be an ideal ... (Read 74 times)

sjones

  • Hero Member
  • *****
  • Posts: 520
on: Jul 7, 2018
Briefly explain first, second, and third normal forms.
 
  What will be an ideal response?

Question 2

Describe and give an example of constraints.
 
  What will be an ideal response?


wergv

  • Sr. Member
  • ****
  • Posts: 365
Reply #1 on: Jul 7, 2018
Answer to Question 1

A table is in the first normal form (1NF) if it contains no repeating groups. It is in the second normal form (2NF) if it is in the first normal form and every non-key attribute is fully dependent on the entire primary key. Finally, a table is in the third normal form (3NF) if it is in the second normal form and no non-key attribute is dependent on another non-key attribute.

Answer to Question 2

Constraints are rules that apply to associations: generalization, a patient can be issued many hospital cards but only one card can be valid at any given time.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

It is believed that humans initially contracted crabs from gorillas about 3 million years ago from either sleeping in gorilla nests or eating the apes.

Did you know?

The average office desk has 400 times more bacteria on it than a toilet.

Did you know?

It is important to read food labels and choose foods with low cholesterol and saturated trans fat. You should limit saturated fat to no higher than 6% of daily calories.

Did you know?

Amphetamine poisoning can cause intravascular coagulation, circulatory collapse, rhabdomyolysis, ischemic colitis, acute psychosis, hyperthermia, respiratory distress syndrome, and pericarditis.

Did you know?

Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.

Normal and mutant homeotic gene action in Arabidopsis Normal and mutant homeotic gene action in Arabidopsis
Sickled and normal red blood cells Sickled and normal red blood cells
A normal pregnancy. A normal pregnancy.
Simple harmonic motion also forms the basis for understanding mechanical waves Simple harmonic motion also forms the basis for understanding mechanical waves
Forms of Sexual Misconduct Forms of Sexual Misconduct
Characteristics of Three Forms of DNA Characteristics of Three Forms of DNA
Video: Virtual Enzyme Kinetics & Lineweaver Burk Plot

For a complete list of videos, visit our video library