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- Support for model constraints
- Support for data skipping indexes
- Support for mutations: `QuerySet.update` and `QuerySet.delete`
- Added functions for working with external dictionaries
- Support FINAL for `ReplacingMergeTree` (chripede)
- Added `DateTime64Field` (NiyazNz)
- Make `DateTimeField` and `DateTime64Field` timezone-aware (NiyazNz)
**Backwards incompatible changes**
Previously, `DateTimeField` always converted its value from the database timezone to UTC. This is no longer the case: the field's value now preserves the timezone it was defined with, or if not specified - the database's global timezone. This change has no effect if your database timezone is set to UTC.