News and Updates

SQLAlchemy 2.0.0b4 Released
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The fourth beta release of SQLAlchemy 2.0 is now available.

Version 2.0.0b4 should be close to ready-to-release quality, in particular for the new Declarative and Python Dataclasses features, which have received much attention within the beta testing period. A variety of issues regarding different styles of annotations and dataclass mappings have been reported and fixed, as well as a range of typing related fixes and improvements to continue to allow for full strict typing without the need for plugins.

There's additionally new improvements within the schema, SQL rendering and SQL type systems and several other improvements and fixes that have either already been released in SQLAlchemy 1.4.44 or will be in SQLAlchemy 1.4.45; the changelogs for 2.0.0b3 and 2.0.0b4 now note additional issues that were backported to the 1.4 series.

The release of 2.0 final is hoped to be mid January of 2023.

The 2.0 series is at this point very close to an approximate "feature freeze", having accumulated a series of changes that will likely lead to a long period of adjustment once released; while the beta releases typically see a few thousand downloads per day, the 1.4 releases average about 1.3 million per day on a weekday, so the download base for SQLAlchemy 2.0 is expected to multiply by at least 10000% within the first few months; new issues and usage questions are expected to be extremely heavy after the release, as 2.0 has most backwards-incompatible changes of any SQLAlchemy release.

Users looking to upgrade to SQLAlchemy 2.0 are encouraged to work through the 2.0 Migration Guide <https://docs.sqlalchemy.org/en/20/changelog/migration_20.html>, which will allow the vast majority of applications that run under SQLAlchemy 1.4 to run completely under SQLAlchemy 2.0; from that point, additional migrations towards new 2.0 Declarative mappings can be undertaken, allowing for full typing support of ORM mappings without plugins. These migrations are are described in the Whats New in SQLAlchemy 2.0? document, along with other migration notes for new features and other less central API changes, such as a new API for PostgreSQL RANGE datatypes.

Links to the detailed changelog for 2.0.0b4 is at Changelog.

SQLAlchemy 2.0.0b4 is available on the Download Page.