Glossary

repository: A migration repository contains manage.py, a configuration file (migrate.cfg) and the database changeset scripts which can be Python scripts or SQL files.
changeset: A set of instructions how upgrades and downgrades to or from a specific version of a database schema should be performed.
ORM: Abbreviation for "object relational mapper". An ORM is a tool that maps object hierarchies to database relations.
version: A version in SQLAlchemy migrate is defined by a changeset. Versions may be numbered using ascending numbers or using timestamps (as of SQLAlchemy migrate release 0.7.2)