Database Management Systems: Core Concepts & Techniques
Key Database Management System Concepts
- Transaction: A sequence of operations performed as a single logical unit of work, ensuring consistency, atomicity, isolation, and durability (ACID).
- Primary Index: Based on the primary key and is ordered.
- Secondary Index: Created on non-primary key attributes and may not be ordered.
- Functional Dependency: Attribute Y is functionally dependent on X if each value of X is associated with exactly one value of Y (X → Y).
- Concurrency Control: Ensures that database
Programming Language Design: Principles, Syntax, and BNF
Programming Language Design Principles
Orthogonality
Orthogonality in programming languages is a principle aimed at providing maximum generality, ensuring there are no restrictions or special cases that combine various language elements. Orthogonality exists when there are no invalid combinations, meaning a programmer should clearly understand if exceptions to a rule exist.
Example of Non-Orthogonality
A common example of a lack of orthogonality is when parameters are automatically passed by value,
Read MoreOperating System Fundamentals: Commands, Architecture, and Services
Operating System Concepts
1. Internal vs. External Commands
Internal commands are built into the command interpreter (like Command Prompt in Windows or Shell in UNIX) and are always loaded into memory when the operating system starts. They execute directly without requiring an external file and are faster. Examples in Windows include DIR, CLS, COPY, and DEL. In UNIX/Linux, examples are CD, PWD, ECHO, and EXIT.
External commands are separate executable files stored in the operating system. They are
Read MoreCore Concepts in Computer Graphics and Virtual Reality
Understanding Pixels, Resolution, and Back-Face Detection
A pixel (short for picture element) is the smallest unit of a digital image or display screen. It represents a single point in a raster image and has a specific color and intensity.
Resolution refers to the number of pixels in an image or display, usually written as width × height (e.g., 1920×1080). Higher resolution means more pixels, which leads to sharper and more detailed images.
Back-Face Detection Algorithm
Back-face detection is a hidden
Read MoreEssential Computer Science Concepts and IT Definitions
System Fundamentals
A system is a set of interrelated parts working together to achieve a common goal.
System Components
- Environment
- Inputs
- Process
- Outputs
Information Systems
An Information System (IS) is a set of elements and procedures designed to improve data processing and elaborate reports, facilitating decision-making to achieve beneficial goals.
Data Processing
Data Processing is a series of elementary operations performed on data to produce results.
Process Flow: Reception → Storage → Processing
Read MoreOperating System Fundamentals: Core Concepts & Components
Understanding Operating Systems
An operating system acts as an intermediary between a user of a computer and the computer hardware.
Scheduling Challenges
Scheduling involves managing machine time. For example, a user might sign up for an hour but finish their job in 45 minutes. This would result in wasted computer idle time. Conversely, a user might run into the problem of not finishing their job in the allotted time.
Operating System Types
- Serial Processing
- Batch Processing
- Multitasking or Time-Sharing