.. _glossary: ******** Glossary ******** .. glossary:: :sorted: repository A migration repository contains :command:`manage.py`, a configuration file (:file:`migrate.cfg`) and the database :term:`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 :term:`changeset`. Versions may be numbered using ascending numbers or using timestamps (as of SQLAlchemy migrate release 0.7.2)