SQLAlchemy: Auto generate class definitions for a legacy database

Question

How can I auto-generate class definitions for SQLAlchemy, including relationships and backref, as the Django-ORM does with manage.py inspectdb?

@Ilja Everilä The question was not written as a tool request. A totally legitimate answer would be an approach for how to write code to do this. As it happens there's a good tool for the job, and that seems a better answer. — Sam Hartman
– Sam Hartman, Commented Sep 25, 2017 at 23:42
Harper: to help the unanswered questions queue to stay low consider to check your own answer. Thanks. — Paolo
– Paolo, Commented Sep 26, 2017 at 1:08

Paolo · Accepted Answer · 2017-09-25 23:37:32Z

22

You can use the python package sqlacodegen for exactly this purpose.

sqlacodegen will inspect the database and generate SQLAlchemy style class definitions for future reference and store them in a file.

Usage:

The generated class definitions are largely correct and include index definitions and constraints (foreign keys).

In my case, it saved me from typing out 19.000 rows of class definitions.

Paolo

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answered Sep 19, 2017 at 13:11

Harper

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3 Comments

Hi @Harper Thanks for sharing, this is a good one but the only problem it works well with SQLAlchemy 1.4 and below Thanks

There are multiple forks of sqlacodegen. I am using sqlacodegen_v2, which is available from pypi.org. It's compatible with sqlalchemy 2.

sqlacodegen was updated 3 weeks ago to work with SQLAlchemy 2.0, version 3.0.0rc5. It's already available on github, but not yet via pypi / pip.