purpose of migration folder in django

The migration folder in Django serves the purpose of managing and applying changes to the database schema. The following steps explain the role of the migration folder:

Creating Initial Migration:
When you create a Django app or make changes to your models, you generate an initial migration using the makemigrations management command.
This command inspects the models in your app and creates migration files in the migration folder that represent the changes to the database schema.
Migration Files:
Each migration file contains Python code that defines the operations to be performed on the database, such as creating or modifying tables, adding or altering fields, and creating indexes.
These files are named with a timestamp to ensure a chronological order of migrations.
Applying Migrations:
The migrate management command is used to apply the migrations and update the database schema accordingly.
This command reads the migration files, executes the operations defined in them, and records the status of each migration in the database.
Database Schema Tracking:
Django maintains a special table in the database called django_migrations to keep track of which migrations have been applied.
This table helps Django determine which migrations need to be applied when you run the migrate command.
Rolling Back Migrations:
If needed, you can use the migrate command with a specific migration name to roll back to a previous state.
This is useful for reverting changes or fixing issues in the database schema.
Migration Dependency Graph:
Django keeps track of dependencies between migrations to ensure that they are applied in the correct order.
The migration files contain information about the dependencies, allowing Django to build a migration dependency graph.
Database Schema Evolution:
The migration system allows for the evolution of the database schema over time as your project evolves.
This enables seamless updates to the database structure without manually writing SQL scripts for each change.
Version Control:
Including the migration files in version control (e.g., Git) ensures that the entire development team can apply the same database changes consistently.
Database Portability:
The migration system abstracts away the specific SQL syntax for different database engines, providing a level of database portability.
Integration with Django Apps:
The migration folder is an integral part of Django apps, enabling developers to manage and version their database schema changes in a structured and automated way.