Database Systems: Architecture, Design, and Normalization
Three-Level Database Architecture
The three-level (three-schema) architecture separates how data is physically stored, logically structured, and viewed by different users. This is the ANSI/SPARC architecture, and it exists mainly to provide data abstraction and data independence.
External, Conceptual, and Internal Levels
- External (View) level: This is the level closest to the users; it defines multiple user views (external schemas). Each view shows only part of the database relevant to that user or
Atmosphere and Weather Exam Cheat Sheet — Key Formulas & Tips
Atmosphere & Weather Exam Cheat Sheet (Super Simple)
Exam-Style Questions — How to Answer (with steps)
1. Temperature Questions
Q: Convert Celsius ↔ Kelvin
How to answer:
- If going from °C → K: add 273.15 (K = °C + 273.15).
- If going from K → °C: subtract 273.15 (°C = K − 273.15).
2. Insolation / Energy Questions
Q: Why is this day warmer/colder?
How to answer:
- Look at the irradiance graph.
- Higher irradiance = more sunlight.
- More sunlight usually = warmer temperatures.
3. Relative Humidity (RH)
Read MoreKautilya’s Arthashastra: Ancient Indian Economic Structure
Ancient Indian Economic Thought and State Power
Ancient Indian economic thought, best represented by Kautilya’s Arthashastra, viewed the economy as a crucial engine for state power (Artha). It stressed a dynamic and balanced system involving agriculture, industry, trade, and state regulation to ensure prosperity and welfare.
Industry and Crafts
Ancient Indian thought recognized the value of manufacturing and specialized crafts as a key source of wealth and national prestige, driving both internal and
Read MoreGlobal Urbanization and City Structures
Historical Development of Cities
Cities in Antiquity
- Around 7,000 years ago, the first cities emerged in China, India, and the Middle East.
- Structure centered around a palace, market, and temple, often protected by a defense wall.
The Greek Polis
- The Greek city-state (*polis*) featured two main urban areas:
- The **Acropolis**: The high, fortified area.
- The **Agora**: The public square and marketplace.
- By the 5th century BCE, the grid plan became common.
Roman Cities
- Characterized by a regular, planned layout
Comparing Language Teaching Methodologies: Form vs. Meaning
Prescriptive Grammar and Language Standards
Prescriptive grammar tries to preserve what is assumed to be the standard language by telling people what rules they should know and how they should speak and write. Therefore, according to prescriptivism, grammar teaching is often seen as establishing the “correct” way of speaking and writing.
Focus on Forms: The Traditional Approach
This option is today considered the traditional approach, although it has not always been viewed that way. Course design
Read MoreEssential Business and Finance Terminology for Professionals
Core Business and Financial Definitions
Commercial Documents and Trade Terms
- Invoice: A legally binding document that is sent after goods or services have been delivered.
- Pro Forma Invoice: Received before payment or ordering; often replaces a quotation.
- Accounting: Systems for recording and classifying business and financial transactions.
- Claims: Demands by customers of an insurance firm for reimbursement following an accident or loss.
- Turnover: The total business done by a company in a given period.
Macroeconomic Equilibrium: IS-LM and WS-PS Analysis
IS-LM Model in a Closed Economy
QUESTION 1:
Consider a closed economy defined by the following equations:
- Consumption (C): 200 + 0.4(Y – T)
- Investment (I): 150 + 0.1Y – 1000(r + x)
- Government Spending (G): 250
- Taxes (T): 100 + 0.2Y
- Real Interest Rate (r): 0.05 (Set by the Central Bank)
- Risk Premium (x): 0.02
Equilibrium Output and the IS Relation
To find the IS relation, we start from the goods market equilibrium condition (Y = Z):
Y = [200 + 0.4(Y – (100 + 0.2Y))] + [150 + 0.1Y – 1000(r + x)] + 250
- Calculating
Database Schema and Advanced SQL Query Solutions
Relational Schema Functional Dependencies (FDs)
Person Entity
Schema: person (per_id, name, zip_code, email, gender, phone)
per_id→name, zip_code, genderemail, phone→per_id
Skill Entity
Schema: skill (sk_code, title, description, level_type)
sk_code→title, description, level_typetitle→description
Company Entity
Schema: company (comp_id, address, zip_code, website, industry_group)
comp_id→address, zip_code, website, industry_groupwebsite, industry_group→comp_id
Takes Entity (Course
Read MoreAnalysis of Frankenstein and Romantic Poetry
The Narrative Structure of Frankenstein
The novel Frankenstein by Mary Shelley uses a frame story structure, where three different stories are connected:
- Robert Walton’s letters begin and end the novel, creating a frame around the main story. Walton is a ship captain writing to his sister about his journey to the Arctic.
- Victor Frankenstein’s story appears when he meets Walton and tells him about his life, his ambition, and the creation of the creature.
- The creature’s story is heard within Victor’s
WBS & RACI (RAM) to Prevent Scope Creep in Projects
WBS, RAM (RACI) and Project Controls
| Concept | Explanation |
|---|---|
Work Breakdown Structure (WBS) |
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Responsibility Assignment Matrix (RAM) |
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