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 (
    82, 10, 9, 142, 59, 60, 62, 141, 27, 22, 
    23, 14, 13, 17, 18, 16, 56, 126, 51295, 
    117, 116, 115, 81, 11, 63, 51326, 135, 
    106, 105, 58, 57, 113, 51344, 120, 51345, 
    119, 51346, 118, 114, 108, 4, 5, 107, 
    6, 51348, 121, 51349, 122, 61, 51350, 
    123, 15, 51496, 51497, 51498
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00200

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "152.16"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 173,
            "rows_produced_per_join": 173,
            "filtered": "100.00",
            "index_condition": "(`test_uchur_k`.`cscart_products_categories`.`product_id` in (82,10,9,142,59,60,62,141,27,22,23,14,13,17,18,16,56,126,51295,117,116,115,81,11,63,51326,135,106,105,58,57,113,51344,120,51345,119,51346,118,114,108,4,5,107,6,51348,121,51349,122,61,51350,123,15,51496,51497,51498))",
            "cost_info": {
              "read_cost": "74.31",
              "eval_cost": "17.30",
              "prefix_cost": "91.61",
              "data_read_per_join": "2K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ]
          }
        },
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "test_uchur_k.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 8,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "43.25",
              "eval_cost": "0.87",
              "prefix_cost": "152.16",
              "data_read_per_join": "45K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`test_uchur_k`.`cscart_categories`.`storefront_id` in (0,1)) and ((`test_uchur_k`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`test_uchur_k`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`test_uchur_k`.`cscart_categories`.`usergroup_ids`))) and (`test_uchur_k`.`cscart_categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}