[GitHub] [airflow] jmcarp opened a new pull request #5244: [AIRFLOW-4464] Add regression test for case-insensitive ids in mysql.

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jmcarp opened a new pull request #5244: [AIRFLOW-4464] Add regression test for case-insensitive ids in mysql.
URL: https://github.com/apache/airflow/pull/5244
 
 
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   ### Jira
   
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   ### Description
   
   - [x] Here are some details about my PR, including screenshots of any UI changes:
   
   By default, string comparisons in mysql are case-insensitive, so the task ids "foo" and "FOO" are treated as identical. This means that a dag with those task ids will fail to schedule with a sqlalchemy `IntegrityError` using mysql, but not postgres or sqlite. This situation probably doesn't happen often, and users probably shouldn't use task ids that are identical except for case, but I think we should improve the behavior here. A few options:
   
   Configure sqlalchemy to use a binary collation for string id columns under mysql so that string comparisons are case-sensitive.
   Require dag and task ids to be unique regardless of case. This would be a breaking change.
   Document that mysql users should configure mysql to use binary collations for string types by default. This would still show users a 500 if the database isn't configured correctly.
   
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   ### Code Quality
   
   - [ ] Passes `flake8`
   

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