Database Recovery Mechanisms Using Transaction Logs
Log-Based Recovery in DBMS
Log-based recovery is a mechanism used in DBMS to restore the database to a consistent state after a system crash or failure. The system maintains a log file stored on stable storage, recording every transaction’s operations before applying them to the database. Each log entry contains the transaction ID, data item name, old value, and new value. Using these logs, the DBMS can reconstruct the database by either undoing incomplete transactions or redoing completed ones.
Major
Read MorePHP Fundamentals: Control Flow, Arrays, and Functions
Core PHP Concepts
Control Statements
Control statements manage the flow of execution based on conditions or repetitions.
Conditional Statements
if...else: Executes code if a condition is true.switch: Selects one of many code blocks to be executed based on a variable’s value.
Looping Statements
for: Used when the number of iterations is known.while: Repeats execution as long as a specified condition remains true.foreach: Specifically designed to iterate through arrays.
File Handling Operations
PHP allows
Read MoreKautilya, Amartya Sen & Gopal Krishna Gokhale — Political Economy
Kautilya (Chanakya)
Kautilya, also known as Chanakya or Vishnugupta, was an ancient Indian polymath, philosopher, economist, jurist, and royal advisor. He served as the chief advisor to the founder of the Maurya Empire, Chandragupta Maurya (c. 375–283 BCE).
Key Work
The Arthashastra (c. 3rd century BCE).
Main Contributions
Political Science and Statecraft
The Arthashastra is a seminal text on statecraft, economic policy, and military strategy. Kautilya’s philosophy revolves around the concept of Matsyanyaya
Geometry Fundamentals and Logic Principles
Chapter 1: Foundations of Geometry
1.1: Points, Lines, and Planes
- Collinear: Points on the same line.
- Coplanar: Points that lie in the same plane.
- Segment: A part of a line consisting of two endpoints and all points between them.
- Endpoint: A point at the end of a segment or the starting point of a ray.
- Ray: Part of a line that extends from one endpoint infinitely in one direction.
- Opposite rays: Two rays that have a common endpoint and form a line.
- Postulate: A statement that is accepted as true without
Corporate Finance: Leverage, Capital Structure, and Investment Appraisal
1. Operational Leverage
Operational leverage refers to the degree to which a firm’s costs are fixed rather than variable. It measures the sensitivity of operating income (EBIT) to changes in sales revenue, given that fixed costs do not change with sales volume in the short run.
Explanation
Fixed vs. Variable Costs: In any business, costs can be divided into fixed costs (such as rent, salaries, machinery depreciation) and variable costs (like raw materials, direct labor that fluctuates with production
Read MoreEssential Facts: UK Culture, History, and Travel Rules
Seaweeds: Sustainable Food Source
Seaweeds are commonly eaten in Asia but are still underused in Western countries. Interest in seaweed is increasing, and they may become important ingredients in Europe because they are nutritious and sustainable.
The Domesday Book: Medieval Record
The Domesday Book was written in 1088 for William the Conqueror. It recorded who owned land in England and how much it was worth, so the king could calculate taxes. It is extremely important because it gives detailed information
Read MoreTransforming Accounting with Blockchain and AI
Blockchain Fundamentals: Bitcoin and Ethereum
Blockchain is a decentralized, distributed ledger system that records transactions in a secure, verifiable, and tamper-resistant manner. It operates without a central authority by relying on cryptography and consensus mechanisms to validate transactions across all nodes on the network. Bitcoin, the first major application of blockchain technology, was designed as a digital currency running on a public and permissionless blockchain. It uses Proof of Work,
Read MoreMicrowave Technology: Applications, Devices, and Transmission Lines
Applications of Microwaves||Common applications (any 5–6 can be written)||–
Radar (Radio Detection and Ranging)||– Satellite communication||– Terrestrial microwave links (point-to-point communication)||–
Microwave ovens (domestic and industrial heating)||– Remote sensing and radiometry||– Medical applications (diathermy, cancer treatment, imaging)||– Radio astronomy and deep-space communication||– Military EW (jamming, guidance, seekers)||Brief explanation of any two:||1.Radar (Radio Detection
Key Concepts in Archaeology and Ancient History
Key Archaeological and Historical Definitions
Defining Artifacts and Eras
- Artifact: An object created or modified by a human being, possessing cultural or time-based importance.
- Stone Age: A prehistoric period lasting approximately 3.4 million years, ending around 4000–2000 BCE. It is divided into three stages: Paleolithic, Mesolithic, and Neolithic.
- Neolithic Age: The final stage of the Stone Age, characterized by the use of polished tools and the spread of agricultural practices.
- Bronze Age: A historic
Array-Based Java Queue Implementation with Example
Array-Based Java Queue Example
Corrected Java Queue Code
The following Java classes implement a simple array-based queue and a tester. Spelling, grammar, and capitalization in comments and output strings have been corrected while preserving all original code logic and content.
class Queue {
private int front; // Front is the index of the first element in the queue
private int rear; // Rear is the index of the last element in the queue
private int maxSize; // maxSize represents the maximum number