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 = 6 
WHERE 
  cscart_products_categories.product_id IN (
    68835, 69400, 69349, 69324, 69291, 69257, 
    69256, 69255, 69123, 68831, 68697, 
    68696, 68879, 68906, 68576, 69176, 
    69175, 69174, 69033, 67842, 69173, 
    69172, 69100, 69099, 69032, 69022, 
    68905, 68408, 68368, 68367, 68695, 
    68547, 68555, 68904, 68903, 68834, 
    68833, 68725, 68605, 68292
  ) 
GROUP BY 
  cscart_products_categories.product_id