image_id    image_path  image
  1          ./images/   aaa
  2          ./images/   bbb
  3          ./images/   ccc

product_id   product_gallery
  1           1,2
  2           3,1
  3           1,2,3

product_id   product_gallery
      1           1,2
      2           1
      3           1,2

product_id   image_id
      1           1
      1           2
      2           1
      3           1
      3           2

id product_id product_gallery
1    1          1
2    1          2
3    2          1