Create 1479-sales-by-day-of-the-week.sql

Author: everthis

1479-sales-by-day-of-the-week.sql

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+# Write your MySQL query statement below
+SELECT i.item_category AS Category,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 2 THEN quantity ELSE 0 END) AS Monday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 3 THEN quantity ELSE 0 END) AS Tuesday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 4 THEN quantity ELSE 0 END) AS Wednesday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 5 THEN quantity ELSE 0 END) AS Thursday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 6 THEN quantity ELSE 0 END) AS Friday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 7 THEN quantity ELSE 0 END) AS Saturday,
+    SUM(CASE WHEN DAYOFWEEK(o.order_date) = 1 THEN quantity ELSE 0 END) AS Sunday
+FROM Items i
+LEFT JOIN Orders o
+ON i.item_id = o.item_id
+GROUP BY i.item_category
+ORDER BY i.item_category;