[AIRFLOW-4038] Restructure database queries on /home

[ffinfo]

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Jira

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  • https://issues.apache.org/jira/browse/AIRFLOW-4038

Description

Restructure database queries in /home

Tests

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Code Quality

• Passes flake8

[XD-DENG]

Seems the only main change here is to use create_session over decorator provide_session ? What's the main advantage of doing this? Or did I miss anything?

Thanks.

[codecov-io]

Codecov Report

Merging #4872 into master will decrease coverage by <.01%.
The diff coverage is 87.5%.

@@            Coverage Diff             @@
##           master    #4872      +/-   ##
==========================================
- Coverage   75.28%   75.28%   -0.01%     
==========================================
  Files         450      450              
  Lines       29026    29023       -3     
==========================================
- Hits        21853    21849       -4     
- Misses       7173     7174       +1

Impacted Files	Coverage Δ
airflow/www/views.py	76.41% <87.5%> (-0.06%)	⬇️
airflow/models/__init__.py	92.81% <0%> (-0.06%)	⬇️

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[codecov-io]

Codecov Report

Merging #4872 into master will decrease coverage by <.01%.
The diff coverage is 87.5%.

@@            Coverage Diff             @@
##           master    #4872      +/-   ##
==========================================
- Coverage   75.28%   75.28%   -0.01%     
==========================================
  Files         450      450              
  Lines       29026    29023       -3     
==========================================
- Hits        21853    21849       -4     
- Misses       7173     7174       +1

Impacted Files	Coverage Δ
airflow/www/views.py	76.41% <87.5%> (-0.06%)	⬇️
airflow/models/__init__.py	92.81% <0%> (-0.06%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 3dd7955...90b2b1b. Read the comment docs.

[ffinfo]

@XD-DENG: Almost, indeed the main thing is to switch from provide_session to create_session. Also the order of statements is changes a bit because dags_query was build up on multiple statements but in-between the error query was there. this is now grouped.

About the switch from provide_session to create_session. Me and @Fokko did a little research and using create_session keeps less time a session locked to a scope. @provide_session on nested sessions can keep the session open for a long time while not really needed. Of course this is bigger then just this call but try to convert things where I can. Has targeting this method to remove the DagBag of the Webserver but I did notice that this call has no usage of DagBag. By this time I already changed the provide_session ;)

[Fokko]

I think the rewrite makes it easier to understand. Any further thoughts @XD-DENG ?

[XD-DENG]

@Fokko LGTM

[Fokko]

Thanks @ffinfo