Create weather-type-in-each-country.sql

Author: kamyu104

MySQL/weather-type-in-each-country.sql

@@ -0,0 +1,13 @@
+# Time:  O(m + n)
+# Space: O(n)
+
+SELECT c.country_name,
+       CASE
+           WHEN AVG(w.weather_state * 1.0) <= 15.0 THEN 'Cold'
+           WHEN AVG(w.weather_state * 1.0) >= 25.0 THEN 'Hot'
+           ELSE 'Warm'
+       END AS weather_type
+FROM Countries AS c
+INNER JOIN Weather AS w ON c.country_id = w.country_id
+WHERE w.day BETWEEN '2019-11-01' AND '2019-11-30'
+GROUP BY c.country_id;