version: "2" plugins: - name: py wasm: url: https://downloads.sqlc.dev/plugin/sqlc-gen-python_1.3.0.wasm sha256: fbedae96b5ecae2380a70fb5b925fd4bff58a6cfb1f3140375d098fbab7b3a3c sql: - schema: "schema.sql" queries: "query.sql" engine: postgresql codegen: - out: src/authors plugin: py options: package: authors emit_sync_querier: true emit_async_querier: true
Option: emit_pydantic_models
By default, sqlc-gen-python will emit dataclasses for the models. If you prefer to use pydantic models, you can enable this option.
with emit_pydantic_models
from pydantic import BaseModel class Author(pydantic.BaseModel): id: int name: str
without emit_pydantic_models
import dataclasses @dataclasses.dataclass() class Author: id: int name: str
Option: emit_str_enum
enum.StrEnum was introduce in Python 3.11.
enum.StrEnum is a subclass of str that is also a subclass of Enum. This allows for the use of Enum values as strings, compared to strings, or compared to other enum.StrEnum types.
This is convenient for type checking and validation, as well as for serialization and deserialization.
By default, sqlc-gen-python will emit (str, enum.Enum) for the enum classes. If you prefer to use enum.StrEnum, you can enable this option.
with emit_str_enum
class Status(enum.StrEnum): """Venues can be either open or closed""" OPEN = "op!en" CLOSED = "clo@sed"
without emit_str_enum (current behavior)
class Status(str, enum.Enum): """Venues can be either open or closed""" OPEN = "op!en" CLOSED = "clo@sed"
Use the :copyfrom command to generate batch insert methods that leverage SQLAlchemy’s executemany behavior via Connection.execute() with a list of parameter mappings.
SQL (example):
-- name: CreateUsersBatch :copyfrom INSERT INTO users (email, name) VALUES ($1, $2);
Generated methods:
def create_users_batch(self, arg_list: List[Any]) -> int async def create_users_batch(self, arg_list: List[Any]) -> int
Call with a list of dicts using positional parameter keys p1..pN (the generator converts $1/@name to :pN):
rows = [ {"p1": "[email protected]", "p2": "Alice"}, {"p1": "[email protected]", "p2": "Bob"}, ] count = queries.create_users_batch(rows) # returns affected rowcount (int)
When a typed params struct is emitted (e.g., many parameters or config thresholds), the method accepts List[<QueryName>Params]. The generator converts items to dicts internally:
@dataclasses.dataclass() class CreateUsersWithDetailsParams: email: str name: str bio: Optional[str] age: Optional[int] active: Optional[bool] count = queries.create_users_with_details([ CreateUsersWithDetailsParams("[email protected]", "Alice", None, None, True), ])
Implementation note: sync and async use conn.execute(sqlalchemy.text(SQL), list_of_dicts) and await async_conn.execute(...) respectively; SQLAlchemy performs efficient batch inserts under the hood.