Relational Schema Design for University and Hospital Systems
ER Diagram Conversion to Relational Schema
The objective is to convert specified Entity-Relationship (ER) diagrams into a functional relational schema, defining appropriate primary and foreign keys.
A. University Database Relational Schema Mapping
Assuming the ER diagram for the University includes the following entities and relationships (based on typical university data models):
Entities Defined:
- Student: (sid, sname, age, major)
- Course: (cid, cname, credits)
- Professor: (pid, pname, department)
- Department:
Java Fundamentals: Structure, Data Types, and Casting
The basic structure of a Java program is based on the concept of classes. Every executable Java program must contain at least one class definition.
Essential Structure of a Java Program
A typical Java application follows this hierarchical structure:
Package Statement (Optional)
The very first statement in a Java source file (if present) is the package statement. It organizes classes into logical groups, preventing naming conflicts.
- Syntax:
package package_name; - Example:
package com.mycompany.app;
- Syntax:
Import
Cybersecurity Essentials: Attacks, Encryption, and Protocols
Common Types of Active Network Attacks
The various types of active attacks are described as follows:
- Masquerade Attack: This occurs when an unauthorized entity pretends to be a legitimate user or system to gain access to resources. For example, an attacker sends a message to a user pretending to be someone else, and the recipient is unaware of the impersonation. A common scenario involves “Darth” sending a message to Alice while pretending to be Bob.
- Replay Attack: This involves the unauthorized capture
Mastering Web Development: HTML, CSS, and JavaScript
Example: Simple HTTP Request (Browser to Server)
GET /index.html HTTP/1.1
Host: www.example.com
User-Agent: Chrome/122.0
Accept: text/htmlThis is the real request your browser sends to the server.
Unit 2: HTML Elements and Structure
1. Basic HTML Structure
<title>My First Page</title>
<h1>Welcome</h1>
<p>This is a paragraph.</p>2. Hyperlink
3. List
- HTML
- CSS
- JavaScript
4. Table
| Name | Age |
|---|---|
| Ankit | 20 |
5. Image
6. Div and Span
This is inline text.
Unit 3: HTML Forms and Multimedia
1.
Read MoreMapReduce Fundamentals: Architecture, Matrix Multiplication, and Distributed Processing
MapReduce Algorithm for Matrix Multiplication
- Input matrices A and B are stored in HDFS.
- Map Phase: Emits key-value pairs for each element multiplication.
- The Mapper emits the key
(i, j), where the value isA[i][k] × B[k][j]. - Shuffle Phase: Groups all intermediate values by the key
(i, j). - Reduce Phase: Sums all values associated with each key
(i, j). - The final result
C[i][j]is the summation:Σ A[i][k] × B[k][j]. - Each Mapper processes a partial multiplication set.
- The Reducer aggregates these partial
Parallel and Distributed Computing Models Explained
Parallel and Distributed Programming Models
Parallel Programming Models
Shared Memory Model: Allows all processors to use the same memory space.
Distributed Memory Model: Uses separate memory for each processor and relies on message passing.
Data Parallelism: Applies the same operation to many data items at once.
Task Parallelism: Runs different tasks in parallel on possibly different data.
Distributed Programming Models
- Client-Server Model: Involves clients requesting services and servers providing them.