SELECT 
  cscart_products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      cscart_products_categories.link_type = "M", 
      CONCAT(
        cscart_products_categories.category_id, 
        "M"
      ), 
      cscart_products_categories.category_id
    )
  ) AS category_ids 
FROM 
  cscart_products_categories 
  INNER JOIN cscart_categories ON cscart_categories.category_id = cscart_products_categories.category_id 
  AND cscart_categories.storefront_id IN (0, 1) 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
WHERE 
  cscart_products_categories.product_id IN (
    65926, 65925, 65924, 65923, 65922, 65921, 
    65920, 65919, 65918, 65917, 65916, 
    65915, 65914, 65913, 65912, 65911, 
    65910, 65909, 65908, 65907, 65906, 
    65905, 65904, 65903, 65902, 65901, 
    65900, 65899, 65898, 65897
  ) 
GROUP BY 
  cscart_products_categories.product_id