What changes are you trying to make? (e.g. Adding or removing code, refactoring existing code, adding reports)

Developed two ERDs (handwritten pdf files) for the bookstore logical model prompts, and finishing the SQL queries in assignment2.sql using DB Browser for SQLite. Composed a short commentary on neural nets article (interesting insights!)

What did you learn from the changes you have made?

How to design a more comprehensive logical data model with entity relationships, including a date and shift tables. I also gained more practice with more challenging SQL concepts such as COALESCE, window functions, string manipulation, UNION, CROSS JOIN, and data manipulation statements like INSERT, UPDATE, and DELETE.

Was there another approach you were thinking about making? If so, what approach(es) were you thinking of?

For some of the window function questions, I wondered about using ROW_NUMBER() instead of DENSE_RANK(), but I think the latter was more effective for instances of multiple purchases on the same market date. For the sales-date comparison query, I think subqueries with MIN() and MAX() could have also worked, but the hints directed us to use CTEs and rank windowed functions.

Were there any challenges? If so, what issue(s) did you face? How did you overcome it?

Everything lol... I also ran into the same issues when rerunning table-creation queries after a table already existed. I added DROP TABLE IF EXISTS product_units; and seemed to fix it.

How were these changes tested?

I ran each query individually and checked the farmersmarket.db directly with the data manipulation queries.

A reference to a related issue in your repository (if applicable)

Checklist

• [ FB] I can confirm that my changes are working as intended

Really interesting module, I felt like I was learning a completely different language!