Database: social_media
Question: State the country where the most positive sentiment tweets were posted.
SQL: SELECT T.Country FROM ( SELECT T2.Country, SUM(T1.Sentiment) AS num FROM twitter AS T1 INNER JOIN location AS T2 ON T1.LocationID = T2.LocationID WHERE T1.Sentiment > 0 GROUP BY T2.Country ) T ORDER BY T.num DESC LIMIT 1