Declaring models

You can define models by inheriting from orm.Model and defining model fields in the fields attribute. For each defined model you need to set two special variables:

• registry an instance of orm.ModelRegistry
• fields a dict of orm fields

You can also specify the table name in database by setting tablename attribute.

import databases
import orm

database = databases.Database("sqlite:///db.sqlite")
models = orm.ModelRegistry(database=database)


class Note(orm.Model):
    tablename = "notes"
    registry = models
    fields = {
        "id": orm.Integer(primary_key=True),
        "text": orm.String(max_length=100),
        "completed": orm.Boolean(default=False),
    }

ORM can create or drop database and tables from models using SQLAlchemy. You can use the following methods:

await models.create_all()

await models.drop_all()

Data types

The following keyword arguments are supported on all field types.

• primary_key - A boolean. Determine if column is primary key.
• allow_null - A boolean. Determine if column is nullable.
• default - A value or a callable (function).
• index - A boolean. Determine if database indexes should be created.
• unique - A boolean. Determine if unique constraint should be created.

All fields are required unless one of the following is set:

• allow_null - A boolean. Determine if column is nullable. Sets the default to None.
• allow_blank - A boolean. Determine if empty strings are allowed. Sets the default to "".
• default - A value or a callable (function).

Special keyword arguments for DateTime and Date fields:

• auto_now - Automatically set the field to now every time the object is saved. Useful for “last-modified” timestamps.
• auto_now_add - Automatically set the field to now when the object is first created. Useful for creation of timestamps.

Default=datetime.date.today() for DateField and datetime.datetime.now() for DateTimeField.

!!! note Setting auto_now or auto_now_add to True will cause the field to be read_only.

The following column types are supported. See TypeSystem for type-specific validation keyword arguments.

• orm.BigInteger()
• orm.Boolean()
• orm.Date(auto_now, auto_now_add)
• orm.DateTime(auto_now, auto_now_add)
• orm.Decimal()
• orm.Email(max_length)
• orm.Enum()
• orm.Float()
• orm.Integer()
• orm.IPAddress()
• orm.String(max_length)
• orm.Text()
• orm.Time()
• orm.URL(max_length)
• orm.UUID()
• orm.JSON()