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import asyncio
import databases
import ormar
import sqlalchemy
from examples import create_drop_database
DATABASE_URL = "sqlite:///test.db"
ormar_base_config = ormar.OrmarConfig(
database=databases.Database(DATABASE_URL),
metadata=sqlalchemy.MetaData(),
)
class Company(ormar.Model):
ormar_config = ormar_base_config.copy(tablename="companies")
id: int = ormar.Integer(primary_key=True)
name: str = ormar.String(max_length=100)
founded: int = ormar.Integer(nullable=True)
class Car(ormar.Model):
ormar_config = ormar_base_config.copy(tablename="cars")
id: int = ormar.Integer(primary_key=True)
manufacturer = ormar.ForeignKey(Company)
name: str = ormar.String(max_length=100)
year: int = ormar.Integer(nullable=True)
gearbox_type: str = ormar.String(max_length=20, nullable=True)
gears: int = ormar.Integer(nullable=True)
aircon_type: str = ormar.String(max_length=20, nullable=True)
@create_drop_database(base_config=ormar_base_config)
async def run_query():
# 1. like in example above
await Car.objects.select_related("manufacturer").fields(
["id", "name", "manufacturer__name"]
).all()
# 2. to mark a field as required use ellipsis
await Car.objects.select_related("manufacturer").fields(
{"id": ..., "name": ..., "manufacturer": {"name": ...}}
).all()
# 3. to include whole nested model use ellipsis
await Car.objects.select_related("manufacturer").fields(
{"id": ..., "name": ..., "manufacturer": ...}
).all()
# 4. to specify fields at last nesting level you can also use set
# - equivalent to 2. above
await Car.objects.select_related("manufacturer").fields(
{"id": ..., "name": ..., "manufacturer": {"name"}}
).all()
# 5. of course set can have multiple fields
await Car.objects.select_related("manufacturer").fields(
{"id": ..., "name": ..., "manufacturer": {"name", "founded"}}
).all()
# 6. you can include all nested fields,
# but it will be equivalent of 3. above which is shorter
await Car.objects.select_related("manufacturer").fields(
{"id": ..., "name": ..., "manufacturer": {"id", "name", "founded"}}
).all()
asyncio.run(run_query())
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