Which region has the highest number of restaurants?
the highest number refers to max(count(id_restaurant))
SELECT T1.region FROM geographic AS T1 INNER JOIN location AS T2 ON T1.city = T2.city GROUP BY T1.region ORDER BY COUNT(T2.id_restaurant) DESC LIMIT 1
database name:db_id restaurant
geographic table geographic Cols: city dtype text, country dtype text, region dtype text, 
generalinfo table generalinfo Cols: id restaurant dtype integer, label dtype text, food type dtype text, city dtype text, review dtype real, 
location table location Cols: id restaurant dtype integer, street number dtype integer, street name dtype text, city dtype text, 
