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 = 275 
WHERE 
  cscart_products_categories.product_id IN (
    10074, 10573, 10577, 10651, 10642, 12529, 
    12515, 12525, 12532, 12523, 10198, 
    10557, 10202, 10556, 10101, 10558, 
    10142, 10134, 10141, 10053, 10138, 
    10130, 9934, 10563, 10569, 10572, 10602, 
    10603, 10137, 12517, 12531, 12526, 
    12509, 10226, 10551, 10550, 10193, 
    10659, 10664, 10666, 10661, 10663, 
    10190, 10657, 10658, 10194, 10692, 
    12530, 12516, 12496, 12519, 12510, 
    10087, 10100, 10698
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00700

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products_categories",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "pt"],
      "key": "pt",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 55,
      "filtered": 100,
      "index_condition": "cscart_products_categories.product_id in (10074,10573,10577,10651,10642,12529,12515,12525,12532,12523,10198,10557,10202,10556,10101,10558,10142,10134,10141,10053,10138,10130,9934,10563,10569,10572,10602,10603,10137,12517,12531,12526,12509,10226,10551,10550,10193,10659,10664,10666,10661,10663,10190,10657,10658,10194,10692,12530,12516,12496,12519,12510,10087,10100,10698)"
    },
    "table": {
      "table_name": "product_position_source",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY", "pt"],
      "key": "PRIMARY",
      "key_length": "6",
      "used_key_parts": ["category_id", "product_id"],
      "ref": [
        "const",
        "noframes_angrybeaver.cscart_products_categories.product_id"
      ],
      "rows": 1,
      "filtered": 100
    },
    "table": {
      "table_name": "cscart_categories",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["category_id"],
      "ref": ["noframes_angrybeaver.cscart_products_categories.category_id"],
      "rows": 1,
      "filtered": 100,
      "attached_condition": "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')"
    }
  }
}