Infi.clickhouse-orm

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- Include alias and materialized fields in queryset results
- Check for database existence, to allow delayed creation
- Added `Database.does_table_exist` method
- Support for `IS NULL` and `IS NOT NULL` in querysets (kalombos)

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- NullableField: take extra_null_values into account in `validate` and `to_python`
- Added `Field.isinstance` method
- Validate the inner field passed to `ArrayField`

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- Add support for compound filters with Q objects (desile)
- Add support for BETWEEN operator (desile)
- Distributed engine support (tsionyx)
- `_fields` and `_writable_fields` are OrderedDicts - note that this might break backwards compatibility (tsionyx)
- Improve error messages returned from the database with the `ServerError` class (tsionyx)
- Added support for custom partitioning (M1hacka)
- Added attribute `server_version` to Database class (M1hacka)
- Changed `Engine.create_table_sql()`, `Engine.drop_table_sql()`, `Model.create_table_sql()`, `Model.drop_table_sql()` parameter to db from db_name (M1hacka)
- Fix parsing of datetime column type when it includes a timezone (M1hacka)
- Rename `Model.system` to `Model._system` to prevent collision with a column that has the same name
- Rename `Model.readonly` to `Model._readonly` to prevent collision with a column that has the same name
- The `field_names` argument to `Model.to_tsv` is now mandatory
- Improve creation time of model instances by keeping a dictionary of default values
- Fix queryset bug when field name contains double underscores (YouCanKeepSilence)
- Prevent exception when determining timezone of old ClickHouse versions (vv-p)

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- Bug fix: add field names list explicitly to Database.insert method (anci)
- Added RunPython and RunSQL migrations (M1hacka)
- Allow ISO-formatted datetime values (tsionyx)
- Show field name in error message when invalid value assigned (tsionyx)
- Bug fix: select query fails when query contains '$' symbol (M1hacka)
- Prevent problems with AlterTable migrations related to field order (M1hacka)
- Added documentation about custom fields.

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- Add `distinct` method to querysets
- Add `AlterTableWithBuffer` migration operation
- Support Merge engine (M1hacka)

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- Fix python3 compatibility (TvoroG)
- Nullable arrays not supported in latest ClickHouse version
- system.parts table no longer includes "replicated" column in latest ClickHouse version