The email index is not used by `get_by_email()` method about fastapi-users-db-sqlalchemy

[frankie567]

Thank you for raising this, @stephane! That's indeed a welcome optimization.

My preference would go for 2, i.e. create a functional index.

I prefer not to rely on custom extension, especially since CIText looks only designed for PostgreSQL.

As for storing the e-mail in lower-case, this is a debate we had some time ago and we purposefully chose to store the e-mails case-sensitive but query them case-insensitive.

If you agree with this, I would be happy to review a PR that creates a lowercased index for e-mails 🙂

[stephane]

Django offers the possibility to provide migrations in third-apps code but I didn't find a similar mechanism with Alembic.

With the new __table_args__, Alembic detects the missing index in my app but displays a warning:

UserWarning: autogenerate skipping functional index ix_user_email_lower; not supported by SQLAlchemy reflection

So I had to manually create the Alembic migration in my project and it's convenient for users of fastapi-users.

op.create_index("ix_user_email_lower", "user", [sa.text("lower(email)")])