Computer Science - IT MCQs
Topic Notes: Computer Science - IT
<p>MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.</p>
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
101
How many distinct phases are typically defined in the standard Systems Development Life Cycle (SDLC)?
Answer:
five phases
The traditional Systems Development Life Cycle (SDLC) is commonly structured into five core phases: planning, analysis, design, implementation, and maintenance. These stages provide a structured framework for managing the development of complex information systems from inception to retirement.
102
What term describes a structured collection of data designed to facilitate efficient access, retrieval, and management?
Answer:
Database
A database is a systematically organized collection of structured information or data, typically stored electronically in a computer system. Databases are managed by Database Management Systems (DBMS) to ensure that data can be easily accessed, updated, and retrieved by users or applications.
103
What is the term for the logical representation of an organization's data structure?
Answer:
Entity-relationship model
The Entity-Relationship (ER) model is a high-level conceptual data model used to represent the logical structure of a database. It visually depicts entities, their attributes, and the relationships between them, serving as a blueprint for the database design before it is implemented in a physical database management system.
104
Which symbol is standard for representing a relationship between two entities in an ERD?
Answer:
Diamond symbol
In the standard Chen notation for Entity-Relationship Diagrams, a diamond-shaped symbol is used to denote the relationship between two or more entities, connecting them to show how they interact within the system.
105
In the context of a relational database, what is the significance of the order of rows?
Answer:
Any
According to the relational model, a relation is defined as a set of tuples. By definition, a set is unordered, meaning the physical or logical order of rows does not affect the data content or the results of queries. Therefore, rows can be stored or retrieved in any order without changing the meaning of the data.
106
Which of the following activities are performed during the logical database design process?
Answer:
All of the above
Logical database design involves translating the conceptual model into a structure that can be implemented. This includes identifying and representing entities, defining the relationships between them, and applying normalization techniques to reduce data redundancy and improve data integrity within the relational schema.
107
What is the most common method for presenting output from a database?
Answer:
report
Reports are the standard way to present database information in a structured, readable format. They allow users to summarize, format, and print data retrieved from the database, making it easier for stakeholders to interpret information. While queries retrieve the data, reports provide the final, formatted output for human consumption.
108
Which factor is most critical for ensuring the accuracy of data stored within a database?
Answer:
underlying logic
The underlying logic, including database design, schema constraints, validation rules, and business logic, is the most important factor for data integrity. While interfaces and applications facilitate interaction, the integrity of the data itself depends on the rules and relationships defined within the database structure to prevent errors and inconsistencies.
109
What is the term for a structured collection of related data tables?
Answer:
Database
A database is defined as an organized collection of structured information or data, typically stored electronically in a computer system. It is designed to allow for the efficient retrieval, management, and updating of related data tables.
110
Which of the following options is generally considered an unsuitable choice for a primary key?
Answer:
First name
A primary key must be unique for every record. A 'First name' is not a suitable primary key because multiple individuals can share the same first name, leading to duplicate values and preventing the database from uniquely identifying specific records.