XD-DENG opened a new pull request #12707:
URL: https://github.com/apache/airflow/pull/12707
- given `filter_dag_ids` is either `allowed_dag_ids`, or intersection of
`allowed_dag_ids` AND `selected_dag_ids`,
hence, no matter if `selected_dag_ids` is `None` or not, `filter_dag_ids`
should ALWAYS be considered into the SQL query.
However, currently, if `selected_dag_ids` is None, the query is actually
getting the full result (then 'filter' at the end).
This means more (unnecessary) data travel between Airflow and DB.
- When we join table A and B with `A.id == B.id` (default is `INNER` join),
if we always confirm ALL A.id is in a specific list,
implicitly ALL ids in the result table are already guaranteed in this
specific list as well.
This is why the two redundant `.filter()` chunks are removed.
I didn't do performance benchmarking, but minor performance improvement
should be expected.
Meanwhile, this change makes the code cleaner.
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