News and Updates

SQLAlchemy release 0.8.4 is now available.

0.8.4 is a relatively early bugfix release, which includes one key feature critical to the recently relased 0.6.1 version of Alembic migrations.

The "reflect unique constraints" feature of 0.9 has been backported to 0.8.4. This feature, which retrieves a list of unique constraint objects from a schema, allows the new Alembic feature of autogenerate for indexes and unique constraints to function fully.

A key bugfix in 0.8.4 involves the QueuePool implementation. An issue was observed where the QueuePool implementation would block when a new connection attempt was stalled; other new connection attempts within concurrent threads would be paused until the stalled attempt completed or errored out. This issue has been resolved, as the section where new connections are created is no longer within a mutex.

The release otherwise includes a small set of minor dialect- and engine-level fixes.

Users should carefully review the Changelog to note which behaviors and issues are affected. We'd like to thank the many contributors who helped with this release.

SQLAlchemy 0.8.4 is available on the Download Page.