Fundamentals Database Management Systems Short Interview And Test Questions
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Q1. Define data.
A collection of raw facts and figures is called data. Data is collected from different sources and is not very meaningful for making decisions. Data may consist of numbers, characters, symbols or pictures, etc. Data is collected for different purposes.
Q2. Define information.
The processed data is called information. It is an organized and processed form of data.
Q3. Define database.
The database can be defined as an organized collection of related data. The word “organized” means that data is stored in such a way that the user can store, manipulate and retrieve data easily. The word “related” means that a database is normally created to store the data about a particular topic.
Q4. Define database management system.
A database management system (DBMS) is a collection of programs that are used to create and maintain a database.
Q5. Define security.
The protection of the database from unauthorized users, which may involve passwords and access restrictions.
Q6. Define data integrity.
The reliability and accuracy of data are called data integrity. The maintenance of the validity and consistency of the database by use of particular constraints that are applied to the data.
Q7. List four examples of database systems.
1. A system that maintains component part details for a car manufacturer
2. An advertising company keeping details of all clients and adverts placed with them
3. A training company keeping course information and participants’ details
4. An organization maintaining all sales order information
Q8. State the purpose of a database.
The purpose of a database is to help people and organizations keep track of things.
Q9. What is metadata? Give an example.
Data about the structure of a database is called metadata. Examples of metadata are the names of tables, names of columns and tables, properties of tables and columns, etc.
Q10. Briefly describes the history of database processing.
In file processing, data was maintained in sequential lists on magnetic tape. Database processing became possible with the availability of direct access disk storage in the 1960s. Using this storage, both the hierarchical data model and network data model were developed. In 1970, E. E. Codd of IBM proposed a relational model that is the standard model used today. Current DBMSs such as 162, Oracle, and SQL. The server is based on a relational model. More recent events include the appearance of microcomputer-based DBMSs, the introduction of Object-Oriented DBMS, and the development of tools such as XML used with database systems over the Internet.
Q11. What does DBMS stand for? List the functions of a DBMS.
DBM DBMS stands for Database Management System. The functions of the DBMS are:
1. Create Database
2. Create Tables
3. Create Supporting Structures
4. Read Database Data
5. Update Database Data Maintain Database Structures
6. Enforce Rules
7. Control Concurrency
8. Provide Security
9. Perform Backup and Recovery
Q12. Contrasts the following terms:
Structural Dependence and Data Dependence Data dependence and data independence Repository and database Structural dependence and data dependence: Any change in the structure of a file such as the addition or deletion of a field requires the modification of all programs using that file. This modification is necessary because access to a file is dependent on its structure. This type of dependence is known as structural dependence. Any change in file data characteristics such as changing a field from integer to decimal requires modification of all programs that access the file. This type of dependence is known as data dependence.
Data dependence and data independence: Data dependence is a tight relationship between data and specific programs. The application programs have to be changed if there is any change in data. Data independence means that data and application programs are separate from each other. The data storage structures and operations can be changed without changing application programs.
Repository and Database: A repository is a centralized storehouse of all data definitions, relationships, and other system components. A database is an organized collection of logically related data.
Q13. Why have databases become the preferred method to store data used by an information
system?
Databases are a common point of access, management, and control. They allow data to be managed as an enterprise-wide resource. The simultaneous access to many users and application programs. They solve many problems associated with separately maintained data stores such as redundancy, inconsistent security, and inconsistent data access methods.
Q14. Give an example of a large-enterprise database application.
A construction company uses a database to keep track of project costs, labor, materials, and schedule. One database supports all of these different applications.
Q15. What were some of the weaknesses of early organizational database applications?
The early organizational database applications were slow and unreliable. DBMS developers did not know efficient ways to provide database access. The programmers did not know how to use new
database technology.
Q16. What is the major drawback of personal databases?
The major drawback of personal databases is that their data cannot be shared with other users, For this reason, they should be limited to special situations where there is not a need to share the data.
Q17. How is the relationship between application programs and DBMS changing over time?
DBMS is gradually taking on more and more of the application programs functions and roles,
Q18. What was the major factor that gave rise to workgroup database applications?
The major factor that gave rise to the workgroup database is the development and acceptance of
LAN technology and products.
Q19. List different categories of databases with examples of each type.
a. Personal computer databases: It is a set of data that describes patient visits, recorded by home healthcare professionals.
b. Workgroup database: It is a database that supports the work of several scientists performing
research on a new drug.
c. Department database: It is a database used by the human resources department of large hospitals.
d. Enterprise database: It is a database that supports SAP enterprise information systems.
Q20. Which problems does data redundancy cause?
Redundant data uses additional storage space and makes it difficult to maintain the accuracy of a database when changes are made
Q21. Why do people use databases for information-handling tasks?
(1) Databases make it easier to store large quantities of information.
(2) Databases make it easier to retrieve information quickly and flexibly.
(3) Databases make it easy to organize and reorganize information.
(4) Databases make it easy to print and distribute information in many ways
Q22. What is the function of application metadata? How does it differ from metadata?
Application metadata is a description of application components such as forms, reports, menus, and queries. It differs from metadata that is a description of the database structure,
Q23. Explain the purpose of forms, reports, queries, and menus.
A form is used to enable users to create, read, modify and delete data. A report is a structured presentation of database data. Queries allow the users to answer questions from the data. Menus are structured presentations of allowed user actions.
Q24. List and describe some of the problems of the traditional file environment.
Following are some problems with the traditional file environment:
1. Data redundancy is the presence of duplicate data in multiple data files. In this situation, confusion Results because the data can have different meanings in different files
2. Program-data dependence is the tight relationship between data stored in files and specific programs required. This dependency is very inefficient, resulting in the need to make changes in many programs when a common piece of data changes.
5. Lack of flexibility means that it is very difficult to create new reports from data when needed.
4. Poor security results from the lack of control over the data because the data are so widespread.
5. Data sharing is virtually impossible because it is distributed in so many different files around the organization,
Q25. List and describe each of the components in the data hierarchy.
The data hierarchy includes bits, bytes, fields, records, files, and databases. Data are organized in a hierarchy that starts with a bit. A bit is represented by either a 0 (off) or a 1 (on). Bits can be grouped to form a byte to represent one character, number, or symbol. Bytes can be grouped to form a field such as a name or a date. Related fields can be grouped to form a record. Related records can be collected to form files. Related files can be organized into a database.
Q26. Name the key personnel involved with databases and briefly describe their roles
The database administrator has both technical and managerial responsibilities over the database resource.-Database programmers are required to create efficient data processing computer code. The end users have a major impact on database design, use, and efficiency.
