SQL to SQLAlchemy: models from a DDL script
What follows is not a mock-up: it is the real output of the generator for the script on the left. You get the same code in the editor under “Codegen → SQLAlchemy”.
The inputschema.sql
CREATE TABLE users (
id BIGINT NOT NULL PRIMARY KEY,
email VARCHAR(255) NOT NULL UNIQUE,
full_name VARCHAR(120),
is_active BOOLEAN NOT NULL,
created_at TIMESTAMP NOT NULL
);
CREATE TABLE orders (
id BIGINT NOT NULL PRIMARY KEY,
user_id BIGINT NOT NULL REFERENCES users(id),
total DECIMAL(12,2) NOT NULL,
note TEXT,
placed_at TIMESTAMP NOT NULL
);What comes outmodels.py
from datetime import datetime
from sqlalchemy import BigInteger, Boolean, DateTime, ForeignKey, Numeric, String, Text
from sqlalchemy.orm import Mapped, mapped_column, relationship
from decimal import Decimal
class Users(Base):
__tablename__ = "users"
id: Mapped[int] = mapped_column(BigInteger, primary_key=True, nullable=False)
email: Mapped[str] = mapped_column(String(255), unique=True, nullable=False)
full_name: Mapped[str | None] = mapped_column(String(120), nullable=True)
is_active: Mapped[bool] = mapped_column(Boolean, nullable=False)
created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
class Orders(Base):
__tablename__ = "orders"
id: Mapped[int] = mapped_column(BigInteger, primary_key=True, nullable=False)
user_id: Mapped[int] = mapped_column(ForeignKey("users.id"), nullable=False)
total: Mapped[Decimal] = mapped_column(Numeric, nullable=False)
note: Mapped[str | None] = mapped_column(Text, nullable=True)
placed_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
users: Mapped["Users"] = relationship()Open the editor
The script stays in the browser: both parsing and generation run on your machine, nothing goes to a server.
How the types land
| in SQL | in the model |
|---|---|
BIGINT | BigInteger |
VARCHAR(255) | String(255) |
BOOLEAN | Boolean |
TIMESTAMP | DateTime |
DECIMAL(12,2) | Numeric |
TEXT | Text |
- Optional field
Mapped[str | None]- Column name
full_name- Relation
ForeignKey("users.id")