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 = 166 
WHERE 
  cscart_products_categories.product_id IN (
    17, 180, 18, 16, 4, 5, 23, 24, 1, 22, 149, 
    190, 189, 3438, 3439, 3440, 3441, 121590, 
    136148, 156245, 169350, 125861, 122330, 
    152282, 146567, 139654, 133778, 149640, 
    159133, 146242, 165619, 121896, 143574, 
    121541, 161803, 151867, 130403, 144684, 
    120464, 144963, 125358, 157738, 154235, 
    137235, 157361, 133193, 157759, 159140, 
    166388, 176206, 135170, 128666, 120703, 
    142104, 162657, 128639, 137145, 145590, 
    160493, 159086, 144380, 153320, 171492, 
    156206
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00192

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.327857853,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products_categories",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "pt",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "loops": 1,
          "rows": 65,
          "cost": 0.115664525,
          "filtered": 100,
          "attached_condition": "cscart_products_categories.product_id in (17,180,18,16,4,5,23,24,1,22,149,190,189,3438,3439,3440,3441,121590,136148,156245,169350,125861,122330,152282,146567,139654,133778,149640,159133,146242,165619,121896,143574,121541,161803,151867,130403,144684,120464,144963,125358,157738,154235,137235,157361,133193,157759,159140,166388,176206,135170,128666,120703,142104,162657,128639,137145,145590,160493,159086,144380,153320,171492,156206)",
          "using_index": true
        }
      },
      {
        "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": [
            "u985510652_ecartify_abhi.cscart_products_categories.category_id"
          ],
          "loops": 65,
          "rows": 1,
          "cost": 0.0589578,
          "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')"
        }
      },
      {
        "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",
            "u985510652_ecartify_abhi.cscart_products_categories.product_id"
          ],
          "loops": 65,
          "rows": 1,
          "cost": 0.1113866,
          "filtered": 100
        }
      }
    ]
  }
}