Update README.md

Author: zainasher42

README.md

@@ -1 +1,186 @@
-# docs-flask-db-migrations
+# Flask Database Migrations with SQLAlchemy & Flask-Migrate
+
+## Introduction
+
+**Flask-Migrate** is an extension that handles database migrations for Flask applications using **Alembic**. It works alongside **SQLAlchemy**, which is an ORM (Object Relational Mapper) that maps Python objects to database tables.
+
+Using Flask-Migrate, you can easily handle version control for your database schema, allowing for smooth database changes and rollbacks over time.
+
+---
+
+## Setup for Different DBMS
+
+Flask-Migrate supports different database management systems. Below are the steps to configure SQLite, MySQL, and PostgreSQL.
+
+### SQLite
+
+SQLite is a lightweight, file-based database suitable for small projects or testing.
+
+1. **Install dependencies**:
+
+   ```bash
+   pip install Flask-SQLAlchemy Flask-Migrate
+   ```
+
+2. **Update `config.py`**:
+
+   ```python
+   # config.py
+   class Config:
+       SQLALCHEMY_DATABASE_URI = 'sqlite:///app.db'  # SQLite URI
+       SQLALCHEMY_TRACK_MODIFICATIONS = False
+   ```
+
+3. **Initialize Flask-Migrate** in `app.py`:
+
+   ```python
+   from flask import Flask
+   from flask_sqlalchemy import SQLAlchemy
+   from flask_migrate import Migrate
+
+   app = Flask(__name__)
+   app.config.from_object('config.Config')
+
+   db = SQLAlchemy(app)
+   migrate = Migrate(app, db)
+   ```
+
+---
+
+### MySQL
+
+1. **Install the MySQL client**:
+
+   ```bash
+   pip install mysqlclient
+   ```
+
+2. **Update `config.py`**:
+
+   ```python
+   # config.py
+   class Config:
+       SQLALCHEMY_DATABASE_URI = 'mysql://username:password@localhost/db_name'  # MySQL URI
+       SQLALCHEMY_TRACK_MODIFICATIONS = False
+   ```
+
+3. **Ensure MySQL is running** and the database exists:
+
+   ```bash
+   mysql -u username -p
+   CREATE DATABASE db_name;
+   ```
+
+---
+
+### PostgreSQL
+
+1. **Install the PostgreSQL client**:
+
+   ```bash
+   pip install psycopg2
+   ```
+
+2. **Update `config.py`**:
+
+   ```python
+   # config.py
+   class Config:
+       SQLALCHEMY_DATABASE_URI = 'postgresql://username:password@localhost/db_name'  # PostgreSQL URI
+       SQLALCHEMY_TRACK_MODIFICATIONS = False
+   ```
+
+3. **Ensure PostgreSQL is running** and create the database:
+
+   ```bash
+   psql -U username
+   CREATE DATABASE db_name;
+   ```
+
+---
+
+## Flask Migrate Full Kickoff
+
+To set up **Flask-Migrate** and apply migrations to your database, follow these steps:
+
+1. **Clone the Git repository**:
+
+   ```bash
+   git clone https://github.com/app-generator/docs-flask-db-migrations
+   cd docs-flask-db-migrations
+   ```
+
+2. **Create and activate a virtual environment**:
+
+   ```bash
+   python3 -m venv venv
+   source venv/bin/activate  # On Windows, use venv\Scripts\activate
+   ```
+
+3. **Install required packages**:
+
+   ```bash
+   pip install -r requirements.txt
+   ```
+
+4. **Configure your database** in `config.py` (choose SQLite, MySQL, or PostgreSQL).
+
+5. **Initialize Flask-Migrate**:
+
+   ```bash
+   flask db init
+   ```
+
+6. **Create your models** in `models.py`:
+
+   ```python
+   from app import db
+
+   class User(db.Model):
+       id = db.Column(db.Integer, primary_key=True)
+       username = db.Column(db.String(150), unique=True, nullable=False)
+       email = db.Column(db.String(150), unique=True, nullable=False)
+   ```
+
+7. **Create the initial migration**:
+
+   ```bash
+   flask db migrate -m "Initial migration"
+   ```
+
+8. **Apply the migration**:
+
+   ```bash
+   flask db upgrade
+   ```
+
+9. **Run the application**:
+
+   ```bash
+   flask run
+   ```
+
+   Your Flask app will be running at `http://127.0.0.1:5000`.
+
+---
+
+## Common Flask-Migrate Commands
+
+- **`flask db init`**: Initializes the migration directory (`migrations/`).
+- **`flask db migrate -m "message"`**: Generates a new migration script.
+- **`flask db upgrade`**: Applies the migration to the database.
+- **`flask db downgrade`**: Rolls back the last migration.
+- **`flask db history`**: Shows the migration history.
+- **`flask db stamp head`**: Marks the current database as being at the latest migration.
+
+---
+
+## Conclusion
+
+In this guide, we’ve covered how to set up **Flask-Migrate** with **SQLAlchemy** for managing database migrations in Flask applications. We’ve also shown how to configure different databases (SQLite, MySQL, PostgreSQL) and run the Flask application with migrations.
+
+By using Flask-Migrate, you can handle database schema changes in a more structured and controlled way. This approach simplifies managing database evolution over time, especially as your project grows.
+
+Feel free to explore the code in the repository and follow the steps to integrate Flask-Migrate into your own Flask applications.
+
+---