docs: create sample notebook to manipulate struct and array data

[chelsea-lin]

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Fixes internal bug: 357587135 🦕

[review-notebook-app]

Check out this pull request on 

See visual diffs & provide feedback on Jupyter Notebooks.

---

Powered by ReviewNB

[tswast]

Line #2.    adj_scores_arr = bbq.array_agg(adj_scores.groupby(level=0))

Could we add a note about ordering? Is the original order preserved? If so, under what conditions?

Reply via ReviewNB

[chelsea-lin]

Added some comments in the code. Please help to double check.

[tswast]

Line #2.    df['NewScores'] = adj_scores_arr

Should we call out that the index needs to be unique? My understanding is that this will do a real JOIN in the SQL, so duplicate keys in the index might cause unexpected results.

Reply via ReviewNB

[chelsea-lin]

Your understanding is correct. Added more comments in the code. Please double check.

[tswast]

Thanks!

[tswast]

Kokoro notebook failure: FAILED notebooks/dataframes/pypi.ipynb:: - RelationError: Table schemas must be equal for set operations. I believe this is internal issue 361145903.