What is the name of each camera lens and the number of photos taken by it? Order the result by the count of photos.
SELECT T1.name ,  count(*) FROM camera_lens AS T1 JOIN photos AS T2 ON T1.id  =  T2.camera_lens_id GROUP BY T1.id ORDER BY count(*)
name of each camera lens refers to T1.name; number of photos taken by it refers to COUNT(*); order by the count refers to ORDER BY COUNT(*);