Converting a query with built-in MySQL functions to flask-sqlalchemy

Question

I have a MySQL query like this:

UPDATE mytable SET is_active=false
WHERE created < DATE_SUB(NOW(), INTERVAL `interval` second)

How can I express it using flask-sqlalchemy 's ORM (ie via the MyTable model)?

Answer 1

This may not be the most elegant solution, but it seems to be working for me:

Base = declarative_base()


class Account(Base):
    __tablename__ = "so62234199"
    id = sa.Column(sa.Integer, primary_key=True)
    created = sa.Column(sa.DateTime)
    interval = sa.Column(sa.Integer)
    is_active = sa.Column(sa.Boolean)

    def __repr__(self):
        return f"<Account(id={self.id}, created='{self.created}')>"


Session = sessionmaker(bind=engine)
session = Session()

account_table = list(Account.metadata.tables.values())[0]
upd = (
    account_table.update()
    .values(is_active=False)
    .where(
        Account.created
        < sa.func.date_sub(
            sa.func.now(),
            sa.text(
                " ".join(
                    ["INTERVAL", str(Account.interval.compile()), "SECOND"]
                )
            ),
        )
    )
)
with engine.connect() as conn:
    conn.execute(upd)

The SQL statement generated is

INFO sqlalchemy.engine.Engine UPDATE so62234199 SET is_active=%s WHERE so62234199.created < date_sub(now(), INTERVAL so62234199.interval SECOND)
INFO sqlalchemy.engine.Engine (0,)