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 (
    1322, 1262, 1317, 1318, 1319, 1320, 1321, 
    1256, 1395, 1396, 1397, 1399, 1406, 
    1407, 1408, 1409, 1410, 1411, 1412, 
    1273, 1425, 1427, 1428, 1429, 1431, 
    1266, 1442, 1447, 1263, 1458, 4526, 
    4527, 4528, 4529, 4530, 4532, 4533, 
    4744, 4745, 4746, 4747, 4750, 4751, 
    4776, 4778, 4780, 4771, 4773, 4767, 
    4788, 4789, 4790
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00327

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "115.41"
    },
    "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": 128,
            "rows_produced_per_join": 128,
            "filtered": "100.00",
            "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`cscart_products_categories`.`product_id` in (1322,1262,1317,1318,1319,1320,1321,1256,1395,1396,1397,1399,1406,1407,1408,1409,1410,1411,1412,1273,1425,1427,1428,1429,1431,1266,1442,1447,1263,1458,4526,4527,4528,4529,4530,4532,4533,4744,4745,4746,4747,4750,4751,4776,4778,4780,4771,4773,4767,4788,4789,4790))",
            "cost_info": {
              "read_cost": "57.81",
              "eval_cost": "12.80",
              "prefix_cost": "70.61",
              "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": [
              "softwarepirmam_hewadelivard_cscart_4.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 6,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "32.00",
              "eval_cost": "0.64",
              "prefix_cost": "115.41",
              "data_read_per_join": "20K"
            },
            "used_columns": [
              "category_id",
              "storefront_id",
              "usergroup_ids",
              "status"
            ],
            "attached_condition": "((`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`storefront_id` in (0,1)) and ((`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`usergroup_ids`))) and (`softwarepirmam_hewadelivard_cscart_4`.`cscart_categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}