CODEWITHSUNDEEP
pythonsqlalchemy
Erik
Erik

Reputation: 3208

Does ORM Model in SQLAlchemy auto create tables?

I am new to sqlalchemy but have used it now successfully to get started.. how ever I feel I am perhaps needlessly doubling up the declartion of my ORM's columns... is the table needed for an ORM object created automatically. ?

from sqlalchemy import Column, Integer, String, DateTime, Boolean
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

TABLE_NAME = "my_hats"


def create_my_hat_table(pg_control):
    pg_control.create_table(TABLE_NAME,
                            Column('creation_datetime', DateTime, primary_key=True, nullable=False),
                            Column('id', Integer, primary_key=True, nullable=False),
                            Column('hat_color', String))


class Hat(Base):
    __tablename__ = TABLE_NAME

    creation_datetime = Column(DateTime, primary_key=True, nullable=False)
    id = Column(Integer, primary_key=True, nullable=False)
    hat_color = Column('hat_color', String)

Elsewhere in my code is a wrapper class with the session object that I use to execute likeso

    def create_table(self, table_name, *args):
        new_table = Table(table_name, self.__meta, *args)

        with self.__db_engine.connect() as conn:
            new_table.create()

Upvotes: 1

Views: 1032

Answers (1)

Erik
Erik

Reputation: 3208

Indeed Snakecharmerb was correct

Calling Base.metadata.create_all(engine) creates the tables declared with Base as their superclass. See also alembic applying incremental changes to a database.

Upvotes: 2

Related Questions