def run_migrations_online():
    engine = engine_from_config(
        config.get_section(config.config_ini_section),
        prefix='sqlalchemy.', poolclass=pool.NullPool
    )

    connection = engine.connect()
    context.configure(
        connection=connection, target_metadata=target_metadata,
        compare_type=True)

    try:
        with context.begin_transaction():
            context.run_migrations()
    finally:
        connection.close()
Run migrations in 'online' mode.
dataset/ETHPy150Open fgimian/flaskage/flaskage/templates/project/db/migrations/env.py/run_migrations_online