[AIRFLOW-4462] Use datetime2 column types when using MSSQL backend

[mortenbpost]

Co-authored-by: mattinbits [email protected]
Co-authored-by: sirVir [email protected]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-4462
  • In case you are fixing a typo in the documentation you can prepend your commit with [AIRFLOW-XXX], code changes always need a Jira issue.
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Description

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This change address the fact that we need to use datetime2 when using MSSQL server as a backend. pyodbc uses microseconds which datetime doesn't support. One of the sideeffects of this is that trigger dag does not work. Details in JIRA.

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Please note that pylint fails for this since it has poor support for alembic. One way to solve this is to ignore the alembic.op module in pylintrc.

Commits

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  1. Subject is separated from body by a blank line
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  4. Subject uses the imperative mood ("add", not "adding")
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  6. Body explains "what" and "why", not "how"

Documentation

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  • All the public functions and the classes in the PR contain docstrings that explain what it does
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Code Quality

• Passes flake8

[ashb]

Thanks @mortenbpost I'm off next week so won't be able to look at this until 12th August.

[sirVir]

Hi @ashb, did you have a chance to look at this PR? Pylint is passing now.

[ashb]

I am not familiar with MSSQL so I'm trusting that this new migration works :)