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, 
  product_position_source.position AS position 
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') 
  LEFT JOIN cscart_products_categories AS product_position_source ON cscart_products_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 1 
WHERE 
  cscart_products_categories.product_id IN (
    31436, 31435, 31434, 31433, 31432, 31431, 
    31430, 31429, 31428, 31427, 31426, 
    31425, 31424, 31423, 14017, 13990, 
    13989, 13968, 13987, 13986, 13985, 
    13983, 13982, 13981, 13980, 13979, 
    13978, 13977, 13976, 13975, 13974, 
    13973, 13972, 13971, 13970, 13969, 
    16527, 13892, 13891, 13882
  ) 
GROUP BY 
  cscart_products_categories.product_id