For each photo, show the id of the camera lens that has taken it.
select camera_lens_id from photos
Which photos were taken with the lens brand 'Sigma' or 'Olympus'?
select * from camera_lens as t1 join photos as t2 on t2.camera_lens_id = t1.id where t1.brand = 'Sigma' or t1.brand = 'Olympus'
Give me the photo names.
select t2.name from camera_lens as t1 join photos as t2 on t2.camera_lens_id = t1.id where t1.brand = 'Sigma' or t1.brand = 'Olympus'