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

Author Question: What are the roles of aggregation and association in relational database? What will be an ideal ... (Read 62 times)

notis

  • Hero Member
  • *****
  • Posts: 596
on: Jul 7, 2018
What are the roles of aggregation and association in relational database?
 
  What will be an ideal response?

Question 2

Design patterns are usually classified based on the type of the problems that they address.
 
  Indicate whether the statement is true or false


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

fraziera112

  • Sr. Member
  • ****
  • Posts: 356
Reply #1 on: Jul 7, 2018
Answer to Question 1

To map to a relational database, aggregation must be flattened into association; that is, the relational model is flat: tables do not own each other and are not composed of each other. This means that aggregation and composition relationships must be changed to association to map to tables. The task is not complicated: the table for the aggregate class provides the primary key, the tables for aggregating classes implement the foreign keys, and the multiplicity stays the same.

Answer to Question 2

TRUE


notis

  • Member
  • Posts: 596
Reply 2 on: Jul 7, 2018
Gracias!

AngeliqueG

  • Member
  • Posts: 343
Reply 3 on: Yesterday
:D TYSM

« previous next »
 

Did you know?

Symptoms of kidney problems include a loss of appetite, back pain (which may be sudden and intense), chills, abdominal pain, fluid retention, nausea, the urge to urinate, vomiting, and fever.

Did you know?

The human body's pharmacokinetics are quite varied. Our hair holds onto drugs longer than our urine, blood, or saliva. For example, alcohol can be detected in the hair for up to 90 days after it was consumed. The same is true for marijuana, cocaine, ecstasy, heroin, methamphetamine, and nicotine.

Did you know?

In 1864, the first barbiturate (barbituric acid) was synthesized.

Did you know?

There used to be a metric calendar, as well as metric clocks. The metric calendar, or "French Republican Calendar" divided the year into 12 months, but each month was divided into three 10-day weeks. Each day had 10 decimal hours. Each hour had 100 decimal minutes. Due to lack of popularity, the metric clocks and calendars were ended in 1795, three years after they had been first marketed.

Did you know?

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

Diet Soda's Consumption's Association with Increased (not Decreased) Prevalence of ... Diet Soda's Consumption's Association with Increased (not Decreased) Prevalence of ...
In Hindu marriages, the roles of husband and wife are firmly established. Neither this woman, whom I ... In Hindu marriages, the roles of husband and wife are firmly established. Neither this woman, whom I ...
The major cortical input and output pathways of the dorsolateral prefrontal association cortex. ... The major cortical input and output pathways of the dorsolateral prefrontal association cortex. ...
The Roles of Lipoproteins The Roles of Lipoproteins
A very light ideal spring stretches by when it is used to hang a 135-N object. What is the ... A very light ideal spring stretches by when it is used to hang a 135-N object. What is the ...
A gene map for chromosome 12 from the NCBI database Map Viewer A gene map for chromosome 12 from the NCBI database Map Viewer
Video: Bacteriophage (Virus) - Mice Experiment

For a complete list of videos, visit our video library