NEW FEATURE

Schema Management

Akron features powerful declarative schema management with automatic migration generation and database synchronization. Define your schema in JSON and let Akron handle the implementation.

✨ Key Features

Declarative schema definition in JSON
Automatic migration generation
Schema change detection
Migration history tracking
Multi-database support
Foreign key relationships

🚀 Quick Workflow

Initialize Project

Run akron db init to create akron.json

Define Schema

Edit akron.json to define your database structure

Generate Migrations

Run akron db makemigrations to create migration files

Apply Changes

Run akron db migrate to update your database

Getting Started

1. Initialize a New Project

Start by initializing a new Akron project. This creates the akron.json schema file and .akron/ directory for migrations.

1# Initialize with SQLite (default)
2akron db init
3
4# Initialize with specific database
5akron db init --provider postgresql --url "postgres://user:pass@localhost:5432/mydb"
6akron db init --provider mysql --url "mysql://user:pass@localhost:3306/mydb"
7akron db init --provider mongodb --url "mongodb://localhost:27017/mydb"

Expected Output

✅ Initialized Akron project
   Provider: sqlite
   Database: sqlite:///app.db
   Schema file: akron.json

📝 Next steps:
   1. Edit akron.json to define your schema
   2. Run 'akron db makemigrations' to generate migrations
   3. Run 'akron db migrate' to apply migrations

2. Define Your Schema

Edit the generated akron.json file to define your database structure with tables, columns, and relationships.

1{
"database": {
  "provider": "sqlite",
  "url": "sqlite:///app.db"
},
"tables": {
  "users": {
    "columns": {
      "id": {
        "type": "int",
        "primary_key": true,
        "auto_increment": true
      },
      "email": {
        "type": "str",
        "unique": true,
        "nullable": false,
        "max_length": 255
      },
      "username": {
        "type": "str",
        "unique": true,
        "nullable": false,
        "max_length": 50
      },
      "created_at": {
        "type": "datetime",
        "default": "CURRENT_TIMESTAMP"
      }
    }
  },
  "posts": {
    "columns": {
      "id": {
        "type": "int",
        "primary_key": true,
        "auto_increment": true
      },
      "title": {
        "type": "str",
        "nullable": false,
        "max_length": 200
      },
      "content": {
        "type": "text",
        "nullable": true
      },
      "author_id": {
        "type": "int",
        "nullable": false
      },
      "published": {
        "type": "bool",
        "default": false
      }
    },
    "foreign_keys": {
      "author_id": {
        "references": "users",
        "column": "id",
        "on_delete": "CASCADE"
      }
    }
  }
}
66}

3. Generate Migrations

After defining your schema, generate migration files that describe the changes needed to transform your database.

1# Generate migrations with auto-generated name
2akron db makemigrations
3
4# Generate migrations with custom name
5akron db makemigrations --name "add_user_posts"

Expected Output

✅ Generated migration: add_user_posts
   File: .akron/add_user_posts.json
   Steps: 2

📋 Migration preview:
   1. Create table 'users'
   2. Create table 'posts'

4. Apply Migrations

Apply the pending migrations to update your database schema.

1# Preview what will be migrated
2akron db migrate --dry-run
3
4# Apply all pending migrations
5akron db migrate

Expected Output

📦 Applying 1 migration(s)...
   Applying add_user_posts.json...
   ✅ Applied add_user_posts.json
✅ All migrations applied successfully!

5. Check Status

Monitor your schema and migration status at any time.

1akron db status

Expected Output

📊 Akron Status
==================================================
Schema file: akron.json
Database: sqlite
URL: sqlite:///app.db
Tables: 2

✅ Schema is up to date

Applied migrations: 1
Pending migrations: 0

Schema Format Reference

Database Configuration

1{
2  "database": {
3    "provider": "sqlite|mysql|postgresql|mongodb",
4    "url": "connection_string"
5  }
6}

Supported Data Types

Basic Types

int - Integer numbers
str - String/VARCHAR
text - Long text content
bool - Boolean values
float - Floating point numbers

Date & Special Types

datetime - Date and time
date - Date only
time - Time only
json - JSON data

Column Constraints

Constraint	Type	Description
primary_key	boolean	Mark column as primary key
auto_increment	boolean	Auto-increment values (integers only)
unique	boolean	Enforce unique constraint
nullable	boolean	Allow NULL values
default	any	Default value for column
max_length	integer	Maximum length (strings)

Foreign Key Relationships

1"foreign_keys": {
"author_id": {
  "references": "users",
  "column": "id",
  "on_delete": "CASCADE|SET_NULL|RESTRICT",
  "on_update": "CASCADE|SET_NULL|RESTRICT"
}
8}

Best Practices

📝 Schema Design

Use meaningful table and column names
Define appropriate constraints (nullable, unique, max_length)
Always define foreign key relationships

🔄 Migration Workflow

Make small, incremental changes
Use descriptive migration names
Always test with --dry-run first

🔗 Related Documentation

→ CLI Commands Overview → Getting Started Guide → Database Support