I went through pretty much every DA-related OA post on the forum and put together this note for my own review. I just finished an OA that felt about PDA level, and reviewing with my own notes really helped, so I'm sharing them here in case they help other people prepping.
About the OA: I'd strongly recommend finishing the Excel questions before doing the SQL ones. For the Excel questions, don't panic — once you actually read and understand what's being asked, you'll find they're all pretty simple. Questions 8 through 15 give you four csv files, each with just one sheet, and merging them all into one workbook makes things a lot easier.
The SQL question was a repeat from the forum: if a fruit category has at least one fruit rated above 4 stars, find the lowest price within that same category.
There are two tables, products and purchase:
products: category, id, product name
purchase: id, product_id, price, stars
Return the lowest price for each category that has at least one customer rating (star) above 4. If a category has no rating above 4, replace the price with 0.
Output:
category | price
apple | 0
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