Here's how to find the answers to both questions using GROUP BY, CASE, and COUNT in SQL:

1. To find the name and count of the manufacturer of the most sold boots in April 2015:

SELECT p.ManufacturerName AS Manufacturer, COUNT(*) AS ManuCount,
  CASE
    WHEN pr.Category = 'Boots' THEN 'Yes'
    ELSE 'No'
  END AS Is_Boots
FROM Sale s
JOIN SaleItem si ON s.SaleID = si.SaleID
JOIN Product pr ON si.ProductID = pr.ProductID
JOIN Manufacturer p ON pr.ManufacturerID = p.ManufacturerID
WHERE pr.Category = 'Boots'
  AND MONTH(s.SaleDate) = 4
  AND YEAR(s.SaleDate) = 2015
GROUP BY p.ManufacturerName, pr.Category
ORDER BY Is_Boots DESC, ManuCount DESC;

2. To find the name and count of the manufacturer of the most sold non-boots item in April 2015, along with the item category:

SELECT p.ManufacturerName AS Manufacturer, COUNT(*) AS ManuCount,
  CASE
    WHEN pr.Category = 'Boots' THEN 'Yes'
    ELSE 'No'
  END AS Is_Boots,
  pr.Category
FROM Sale s
JOIN SaleItem si ON s.SaleID = si.SaleID
JOIN Product pr ON si.ProductID = pr.ProductID
JOIN Manufacturer p ON pr.ManufacturerID = p.ManufacturerID
WHERE pr.Category != 'Boots'
  AND MONTH(s.SaleDate) = 4
  AND YEAR(s.SaleDate) = 2015
GROUP BY p.ManufacturerName, pr.Category
ORDER BY Is_Boots DESC, ManuCount DESC;

These queries should provide you with the answers you need using GROUP BY, CASE, and COUNT. The results will show you the top-selling brand of boots in Row 1 and the top-selling brand of non-boots in Row 10.

Sources

Chapter 2 Database questions Flashcards - QuizletMIS 180 SQL Chapter 2-4 Flashcards - QuizletQuestion: I need help with my hw please. this is all the info i was given, thank you! - CheggSQL database.docx - Show sales information for sneakers whose color is not Black or Blue. Select * From SimplifiedSales Where category = Sneakers AndSolved For each information request below, formulate a | Chegg.com[Solved] Assignment 4 For each information request below, formulate a... - Course Hero

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