How many products have the characteristic named "hot"
SELECT count ( * )  FROM products AS t1 JOIN product_characteristics AS t2 ON t1.product_id   =   t2.product_id JOIN CHARACTERISTICS AS t3 ON t2.characteristic_id   =   t3.characteristic_id WHERE t3.characteristic_name   =   "hot"
products with the characteristic named 'hot' refers to JOIN condition on characteristics table where characteristic_name = 'hot'; counting products refers to SELECT COUNT(*)