This topic contains a solution. Click here to go to the answer
« previous next »

Author Question: Describe primary and foreign keys. How do they differ? When and how they are needed? What will be ... (Read 60 times)

cartlidgeashley

  • Hero Member
  • *****
  • Posts: 572
on: Jul 7, 2018
Describe primary and foreign keys. How do they differ? When and how they are needed?
 
  What will be an ideal response?

Question 2

Telecommuting is facilitated by all of the following except:
 
  A) privacy laws.
  B) low costs for personal computing products.
  C) Internet connectivity.
  D) software to facilitate remote collaboration.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Ptupou85

  • Sr. Member
  • ****
  • Posts: 334
Reply #1 on: Jul 7, 2018
Answer to Question 1

A primary key is an attribute or a set of attributes whose values uniquely identify a row. The relationship between entities in different tables is established through foreign keys. The foreign key is an attribute in one table, the value of which must match the value of a primary or an alternate key in another table. Unlike primary keys, foreign keys are not required and do not, necessarily, identify a row uniquely. Like primary keys, a foreign key can be composite, consisting of more than one attribute.

Answer to Question 2

A


cartlidgeashley

  • Member
  • Posts: 572
Reply 2 on: Jul 7, 2018
Great answer, keep it coming :)

dreamfighter72

  • Member
  • Posts: 355
Reply 3 on: Yesterday
:D TYSM

« previous next »
 

Did you know?

Atropine, along with scopolamine and hyoscyamine, is found in the Datura stramonium plant, which gives hallucinogenic effects and is also known as locoweed.

Did you know?

Certain chemicals, after ingestion, can be converted by the body into cyanide. Most of these chemicals have been removed from the market, but some old nail polish remover, solvents, and plastics manufacturing solutions can contain these substances.

Did you know?

The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.

Did you know?

Hypertension is a silent killer because it is deadly and has no significant early symptoms. The danger from hypertension is the extra load on the heart, which can lead to hypertensive heart disease and kidney damage. This occurs without any major symptoms until the high blood pressure becomes extreme. Regular blood pressure checks are an important method of catching hypertension before it can kill you.

Did you know?

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

Primary neurulation Primary neurulation
Select of Primary and Secondary Procedures Select of Primary and Secondary Procedures
General location of the primary auditory cortex and areas of secondary auditory cortex. Most ... General location of the primary auditory cortex and areas of secondary auditory cortex. Most ...
"No Oven Needed" Energy Bars Try this recipe as an inexpensive alternative to commercial ... "No Oven Needed" Energy Bars Try this recipe as an inexpensive alternative to commercial ...
How many grams of tartaric acid, H2C4H4O6, (molar mass = 150.10 g) are needed to How many grams of tartaric acid, H2C4H4O6, (molar mass = 150.10 g) are needed to
Describe the Conceptual Forecasting Framework in your own words. Describe the Conceptual Forecasting Framework in your own words.
Video: Effect of blood chemistry - stimuli, hyperventilation response and hypoventilation response

For a complete list of videos, visit our video library