MySQL

MySQL works through SQLAlchemy's async dialects. Kernia does not need a separate MySQL adapter package; install kernia-sqlalchemy and the async driver that matches your deployment.

Installation

uv add kernia kernia-sqlalchemy sqlalchemy asyncmy alembic

Use aiomysql instead of asyncmy if that is the driver your platform supports.

Configuration

from sqlalchemy.ext.asyncio import create_async_engine
from kernia_sqlalchemy import sqlalchemy_adapter

engine = create_async_engine(
    "mysql+asyncmy://user:password@localhost:3306/app",
    pool_pre_ping=True,
)
adapter = sqlalchemy_adapter(engine)

Schema details

Review generated column sizes for tokens, provider IDs, email fields, and JSON fields. Some MySQL-compatible services differ in JSON support, index length behavior, collation defaults, and timestamp precision.

Use UTC consistently. If your driver or database has timezone options, set them explicitly and test session expiration around daylight-saving changes.

Migrations

Generate through kernia generate, commit the Alembic migration, and run it through your normal migration process:

uv run kernia generate --app app.auth:auth --output alembic/versions/0001_kernia.py
alembic upgrade head

Production notes

• Use a case-insensitive email strategy deliberately. Do not rely on accidental collation behavior.
• Keep API key hashes, session tokens, and verification tokens indexed.
• Test JSON plugin fields on your exact MySQL-compatible service.
• Monitor slow queries on session lookup and account linking.

Troubleshooting

• If JSON fields fail, confirm your target MySQL version supports JSON columns.
• If unique indexes fail on long strings, adjust generated migration column lengths before applying.
• If sessions expire unexpectedly, check timezone conversion and integer timestamp handling.