(Homework Solution): Question 1 Define a database system.[5 marks] b. a. Within the context of database systems,

Question 1 Define a database system.[5 marks] b. a. Within the context of database systems, explain what is meant by each of the following terms i. Data independence ii Data redundancy iii. Data integrity iv. Data security [5 marks] [5 marks] [5 marks] [5 marks] ITOTAL 25 MARKS] Question2 Distinguish between different types of office automation applications [25MARKS]

Attend to question 1

Question 1 Define a database system.[5 marks] b. a. Within the context of database systems, explain what is meant by each of the following terms i. Data independence ii Data redundancy iii. Data integrity iv. Data security [5 marks] [5 marks] [5 marks] [5 marks] ITOTAL 25 MARKS] Question2 Distinguish between different types of office automation applications [25MARKS]

Expert Answer

answers

Question 1:

a.)

Ans: A database is simply an organized collection of related data, typically stored on disk or any storage medium that can be used remotely or directly, and accessible by possibly many concurrent users. Databases are generally separated into application areas. For example, one database may contain Human Resource (employee and payroll) data; another may contain sales data; another may contain accounting data; and so on.

To mantail the databese system, we need a database managemant system(DBMS). DBMS is a set of programs that manages any number of databases.

A DBMS is responsible for:

  • Data Independence.
  • Data Reduncancy.
  • Data Integrity.
  • Data Security.

etc.

b.)

Ans:

i)    Data Independence

A database system normally contains a lot of data in addition to users’ data. For example, it stores data about data, known as metadata, to locate and retrieve data easily. It is rather difficult to modify or update a set of metadata once it is stored in the database. But as a DBMS expands, it needs to change over time to satisfy the requirements of the users. If the entire data is dependent, it would become a tedious and highly complex job. Data itself follows a layered architecture, so that when we change data at one layer, it does not affect the data at another level. This data is independent but mapped to each other.

There are two types of data independency

  • Logical independence
  • Physical Independence

ii)    Data Redundency

Data redundancy is the repetition or superfluity of data. Data redundancy data is an common issue in computer data storage and database systems. Redundancy in database means that some data fields are repeated in the database.

This data repetition may occur either if a field is repeated in two or more tables or if the field is repeated within the table.Data can appear multiple times in a database for a variety of reasons. For example, a shop may have the same customer’s name appearing several times if that customer has bought several different products at different dates.

iii) Data Intrgrity

Data integrity is the completeness, accuracy and consistency of data. This can be indicated by the absence of alteration between two instances or between two updates of a data record, meaning data is intact and unchanged. Data integrity is usually imposed during the database design phase through the use of standard procedures and rules. Data integrity can be maintained through the use of various error-checking methods and validation procedures.

Data integrity is enforced in both hierarchical and relational database models. The following three integrity constraints are used in a relational database structure to achieve data integrity:

  • Entity Integrity: This is concerned with the concept of primary keys. The rule states that every table must have its own primary key and that each has to be unique and not null.
  • Referential Integrity: This is the concept of foreign keys. The rule states that the foreign key value can be in two states. The first state is that the foreign key value would refer to a primary key value of another table, or it can be null. Being null could simply mean that there are no relationships, or that the relationship is unknown.
  • Domain Integrity: This states that all columns in a relational database are in a defined domain.

iv)    Data Security

Data security is an imperative aspect of database system. It is of particular importance in distributed systems because of large number of users, fragmented and replicated data, multiple sites and distributed control.

  • Availability loss: Availability loss refers to non-availability of database objects by legitimate users.
  • Integrity loss: Integrity loss occurs when unacceptable operations are performed upon the database either accidentally or any other reason. This may happen while creating, inserting, updating or deleting data. It results in corrupted data leading to incorrect decisions.
  • Confidentiality loss: Confidentiality loss occurs due to unauthorized or unintentional disclosure of confidential information. It may result in illegal actions, security threats and loss in public confidenc
iWriteHomework
Order NOW for a 10% Discount
Pages (550 words)
Approximate price: -

Why Us?

Top Quality and Well-Researched Papers

All ourbpapers are written from scratch. In fact, Clients who ask for paraphrasing services are highly discouraged. We have writers ready to craft any paper from scratch and deliver quality ahead of time.

Professional and Experienced Academic Writers

Our writers keeps you posted on your papers progress - providing you with paper outline/draft. You are also at liberty to communicate directly with your writer.

Free Unlimited Revisions

If you think we missed something, send your order for a free revision. You have 10 days to submit the order for review after you have received the final document. You can do this yourself after logging into your personal account or by contacting our support.

Prompt Delivery and 100% Money-Back-Guarantee

All papers are always delivered on time, in many cases quite ahead of time. In case we need more time to master your paper, we may contact you regarding the deadline extension. In case you cannot provide us with more time, a 100% refund is guaranteed.

Original & Confidential

We use several writing tools checks to ensure that all documents you receive are free from plagiarism. Our editors carefully review all quotations in the text. We also promise maximum confidentiality in all of our services.

24/7 Customer Support

Our support agents are available 24 hours a day 7 days a week and committed to providing you with the best customer experience. Get in touch whenever you need any assistance.

Try it now!

Calculate the price of your order

Total price:
$0.00

How it works?

Follow these simple steps to get your paper done

Place your order

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

No need to work on your paper at night. Sleep tight, we will cover your back. We offer all kinds of writing services.

Essays

Essay Writing Service

No matter what kind of academic paper you need and how urgent you need it, you are welcome to choose your academic level and the type of your paper at an affordable price. We take care of all your paper needs and give a 24/7 customer care support system.

Admissions

Admission Essays & Business Writing Help

An admission essay is an essay or other written statement by a candidate, often a potential student enrolling in a college, university, or graduate school. You can be rest assurred that through our service we will write the best admission essay for you.

Reviews

Editing Support

Our academic writers and editors make the necessary changes to your paper so that it is polished. We also format your document by correctly quoting the sources and creating reference lists in the formats APA, Harvard, MLA, Chicago / Turabian.

Reviews

Revision Support

If you think your paper could be improved, you can request a review. In this case, your paper will be checked by the writer or assigned to an editor. You can use this option as many times as you see fit. This is free because we want you to be completely satisfied with the service offered.

× Contact Live Agents