SQLAlchemy : remove all foreign keys constraints

remove_foreign_keys.py

def remove_foreign_keys(db):
    log("Dropping all foreign key constraints from archive database")

    inspector = reflection.Inspector.from_engine(db.engine)
    fake_metadata = MetaData()

    fake_tables = []
    all_fks = []

    for table_name in db.metadata.tables:
        fks = []
        for fk in inspector.get_foreign_keys(table_name):
            if fk['name']:
                fks.append(ForeignKeyConstraint((),(),name=fk['name']))
        t = Table(table_name, fake_metadata, *fks)
        fake_tables.append(t)
        all_fks.extend(fks)

    connection = db.engine.connect()
    transaction = connection.begin()
    for fkc in all_fks:
        connection.execute(DropConstraint(fkc))
    transaction.commit()

DropConstraint just saved my life! And the opposite is AddConstraint which emits an ALTER TABLE CREATE CONSTRAINT ...

@mikeghen Thank you, just saved my life too! But, I use sqlalchemy 1.4.39 and I edit the code as follow

From:

inspector = reflection.Inspector.from_engine(db.engine)

To:

from sqlalchemy import inspect
inspector = inspect(engine)