Author Question: A data flow to a data store means update. Indicate whether the statement is true or ... (Read 138 times)

ss2343

  • Hero Member
  • *****
  • Posts: 548
A data flow to a data store means update.
 
  Indicate whether the statement is true or false

Question 2

Discuss some of the disadvantages of file processing systems.
 
  What will be an ideal response?


aruss1303

  • Sr. Member
  • ****
  • Posts: 314
Answer to Question 1

TRUE
Explanation: A data flow has only one direction of flow between symbols. It may flow in both directions between a process and a data store to show a read before an update. The latter is usually indicated, however, by two separate arrows because the read and update usually happen at different times.
CL

Answer to Question 2

File processing systems have several disadvantages, including:
1. Program-data dependenceThe program is tied to the underlying data. Whenever the data changes, (in the sense of structurally), then the program must be modified.
2. Duplication of dataApplications are often developed separately, resulting in duplicate data.
3. Limited data sharingThis is closely related to disadvantage 2, since often applications are developed in a silo. So, for example, the accounting department might develop an application which uses some of the same data as another department. However, there is no data sharing, so two sets of data are maintained.
4. Excessive program maintenance and lengthy development timesSince the programmer has to write all of the low-level file I/O for the application, this adds to the complexity of the application. Also, since the program might need maintenance whenever there is a change to the attributes of the data, there is a need for a lot of program maintenance.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question


 

Did you know?

According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.

Did you know?

The tallest man ever known was Robert Wadlow, an American, who reached the height of 8 feet 11 inches. He died at age 26 years from an infection caused by the immense weight of his body (491 pounds) and the stress on his leg bones and muscles.

Did you know?

After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.

Did you know?

The average older adult in the United States takes five prescription drugs per day. Half of these drugs contain a sedative. Alcohol should therefore be avoided by most senior citizens because of the dangerous interactions between alcohol and sedatives.

Did you know?

Studies show that systolic blood pressure can be significantly lowered by taking statins. In fact, the higher the patient's baseline blood pressure, the greater the effect of statins on his or her blood pressure.

For a complete list of videos, visit our video library