GCSE Computer Science:
Do you want to save hours of lesson preparation time? Get your evenings and weekends back and focus your time where it's needed! Be fully prepared with presentations, notes, activities, and more.
All Computer Science topics are covered, and each module comes complete with:
- Classroom Presentations
- Revision Notes
- Activities & Quizzes
- Mind Maps, Flashcards & Glossaries
Frequently Asked Questions
What is a Database Management System (DBMS)?
A Database Management System (DBMS) is a software application that enables users to create, manage, and manipulate databases. It provides a centralized location for storing, retrieving, and updating data while ensuring data consistency, integrity, and security. A DBMS also allows multiple users to access the data concurrently and provides tools for data backup and recovery in case of data loss.
What are the main types of DBMS?
There are four main types of DBMS:
- Hierarchical DBMS: Organizes data in a tree-like structure with parent-child relationships.
- Network DBMS: Represents data as a graph with nodes and edges, allowing for many-to-many relationships between records.
- Relational DBMS: Stores data in tables with rows and columns, where relationships are formed based on matching values in different tables.
- Object-Oriented DBMS: Combines database capabilities with object-oriented programming, allowing data to be stored as objects with methods and attributes.
What is the role of a Database Administrator (DBA) in a DBMS?
A Database Administrator (DBA) is responsible for managing and maintaining a DBMS. Their main duties include installing and configuring the DBMS, ensuring data security, creating and managing user accounts with appropriate access privileges, monitoring system performance, optimizing queries, and implementing backup and recovery plans.
What are the ACID properties in a DBMS?
ACID (Atomicity, Consistency, Isolation, Durability) properties are crucial for maintaining database reliability and ensuring smooth operations in a multi-user environment.
- Atomicity: A transaction must either be completed in its entirety or not executed at all.
- Consistency: A transaction must ensure the database transitions from one consistent state to another.
- Isolation: Each transaction should be isolated from other concurrent transactions, ensuring no interference occurs.
- Durability: Once a transaction is committed, its changes should be permanent, even in the case of a system failure.
What is a SQL and how is it used in a DBMS?
SQL (Structured Query Language) is a standardized programming language used to interact with a relational DBMS. It allows users to define, manipulate, and retrieve data stored in the database. SQL is used to perform various tasks such as creating and modifying tables, inserting, updating, and deleting records, and querying the database for specific information. SQL is widely used across different relational DBMSs due to its simplicity and powerful capabilities.