Update readme.md

iamAntimPal · iamAntimPal · commit 16ca2730fdcf · 2025-03-31T12:06:47.000+05:30
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+Below is a well-structured `README.md` that documents the database schema, sample data, and queries for the provided SQL code. This file can be added to your repository for clarity and organization.
+
+```md
+# Prosnal Database Example
+
+This repository contains SQL scripts for creating and populating a sample database called `prosnal_database`. The database includes multiple tables and queries demonstrating joins and calculations. The following sections describe the database schema, sample data insertion, and example queries.
+
+---
+
+## Database and Tables
+
+### 1. Create and Use Database
+```sql
+CREATE DATABASE IF NOT EXISTS prosnal_database;
+USE prosnal_database;
+```
+- This command creates the database `prosnal_database` if it does not exist and sets it as the current working database.
+
+---
+
+### 2. Employees Table
+```sql
+CREATE TABLE IF NOT EXISTS Employees (
+    Id INT,
+    Name VARCHAR(255),
+    Salary INT,
+    Department VARCHAR(255)
+);
+```
+- **Description:**  
+  Contains employee information such as `Id`, `Name`, `Salary`, and `Department`.
+
+#### Sample Data:
+```sql
+INSERT INTO Employees (Id, Name, Salary, Department)
+VALUES (1, 'John Doe', 50000, 'HR'),
+       (2, 'Jane Smith', 60000, 'Finance'),
+       (3, 'Mike Johnson', 70000, 'IT'),
+       (4, 'Sarah Black', 60000, 'Finance'),
+       (5, 'David White', 70000, 'IT');
+```
+
+---
+
+### 3. Projects Table
+```sql
+CREATE TABLE IF NOT EXISTS Projects (
+    Id INT,
+    Name VARCHAR(255),
+    Department VARCHAR(255)
+);
+```
+- **Description:**  
+  Contains project details including project `Id`, `Name`, and the corresponding `Department`.
+
+#### Sample Data:
+```sql
+INSERT INTO Projects (Id, Name, Department)
+VALUES (1, 'Project A', 'IT'),
+       (2, 'Project B', 'Finance'),
+       (3, 'Project C', 'IT');
+```
+
+---
+
+### 4. EmployeeProjects Table
+```sql
+CREATE TABLE IF NOT EXISTS EmployeeProjects (
+    EmployeeId INT,
+    ProjectId INT
+);
+```
+- **Description:**  
+  Associates employees with projects.
+
+#### Sample Data:
+```sql
+INSERT INTO EmployeeProjects (EmployeeId, ProjectId)
+VALUES (1, 1),
+       (1, 2),
+       (2, 1),
+       (3, 1),
+       (3, 3),
+       (4, 2),
+       (5, 1);
+```
+
+---
+
+### 5. Users and Sessions Tables
+#### Users Table
+```sql
+CREATE TABLE users (
+    id INT PRIMARY KEY,
+    name VARCHAR(50),
+    email VARCHAR(100)
+);
+```
+- **Description:**  
+  Contains user information with unique `id`, `name`, and `email`.
+
+#### Sample Data:
+```sql
+INSERT INTO users (id, name, email)
+VALUES (1, 'John Doe', 'john.doe@example.com'),
+       (2, 'Jane Smith', 'antima@example.com');
+```
+
+#### Sessions Table
+```sql
+CREATE TABLE sessions (
+    id INT PRIMARY KEY,
+    user_id INT,
+    session_date DATE
+);
+```
+- **Description:**  
+  Records session data with session `id`, associated `user_id`, and the `session_date`.
+
+#### Sample Data:
+```sql
+INSERT INTO sessions (id, user_id, session_date)
+VALUES (1, 1, '2022-01-01'),
+       (2, 1, '2022-01-02'),
+       (3, 2, '2022-01-03');
+```
+
+---
+
+### 6. Products and Orders Tables
+#### Products Table
+```sql
+CREATE TABLE IF NOT EXISTS products (
+    id INT PRIMARY KEY,
+    name VARCHAR(50),
+    price DECIMAL(10, 2)
+);
+```
+- **Description:**  
+  Contains product details such as `id`, `name`, and `price`.
+
+#### Sample Data:
+```sql
+INSERT INTO products (id, name, price)
+VALUES (1, 'Product A', 10.99),
+       (2, 'Product B', 20.99),
+       (3, 'Product C', 30.99);
+```
+
+#### Orders Table
+```sql
+CREATE TABLE IF NOT EXISTS orders (
+    id INT PRIMARY KEY,
+    product_id INT,
+    quantity INT
+);
+```
+- **Description:**  
+  Stores order details including order `id`, associated `product_id`, and order `quantity`.
+
+#### Sample Data:
+```sql
+INSERT INTO orders (id, product_id, quantity)
+VALUES (1, 1, 5),
+       (2, 2, 3),
+       (3, 3, 1),
+       (4, 1, 2),
+       (5, 2, 4);
+```
+
+---
+
+## Example Queries
+
+### Query 1: List Employee Projects
+Join the **Employees**, **EmployeeProjects**, and **Projects** tables to list each employee's project details.
+```sql
+SELECT e.Name AS EmployeeName, e.Department, p.Name AS ProjectName, p.Department
+FROM Employees e
+JOIN EmployeeProjects ep ON e.Id = ep.EmployeeId
+JOIN Projects p ON ep.ProjectId = p.Id;
+```
+
+### Query 2: List User Sessions
+Join the **users** and **sessions** tables to list the session dates for each user.
+```sql
+SELECT u.name AS user_name, s.session_date
+FROM users u
+JOIN sessions s ON u.id = s.user_id;
+```
+
+### Query 3: Calculate Order Totals
+Join the **products** and **orders** tables to calculate the total price for each order.
+```sql
+SELECT p.name AS product_name, o.quantity, p.price * o.quantity AS total_price
+FROM products p
+JOIN orders o ON p.id = o.product_id;
+```
+
+---
+
+## File Structure
+```
+Prosnal_Database/
+│── README.md
+│── schema.sql        -- Contains all CREATE TABLE and INSERT statements.
+│── queries.sql       -- Contains sample SELECT queries.
+│── sample_data.csv   -- (Optional) CSV files for sample data.
+```
+
+---
+
+## Useful Links
+- [MySQL Documentation](https://dev.mysql.com/doc/)
+- [W3Schools SQL Tutorial](https://www.w3schools.com/sql/)
+- [Pandas Documentation](https://pandas.pydata.org/docs/)
+
+---
+
+This `README.md` provides a comprehensive overview of the database creation, data insertion, and query examples. Let me know if you need any modifications or further details!
+```
+
+This documentation should help users understand the purpose of each table and query, and it organizes your code in a clear and accessible way.
