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()

from sqlalchemy.engine import reflection
from sqlalchemy import MetaData, Table, ForeignKeyConstraint
from sqlalchemy.schema import DropConstraint

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)