Write SQL query to solve given problem: Identify the percent of long reviews among all 5-star reviews given to businesses by the Yelp users.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT CAST(SUM(CASE WHEN review_length = 'Long' THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(review_length) FROM Reviews WHERE review_stars = 5