CREATE TABLE camera_lens (name VARCHAR, id VARCHAR)
CREATE TABLE photos (camera_lens_id VARCHAR)

What are the names of the cameras that have taken picture of the most mountains?
SELECT T2.name FROM photos AS T1 JOIN camera_lens AS T2 ON T1.camera_lens_id = T2.id GROUP BY T2.id ORDER BY COUNT(*) DESC LIMIT 1
SELECT "T2"."name" FROM "photos" AS "T1" JOIN "camera_lens" AS "T2" ON "T1"."camera_lens_id" = "T2"."id" GROUP BY "T2"."id" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1