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 (
    908, 134, 1142, 853, 1146, 1145, 1144, 
    1143, 856, 1540, 1541, 1542, 1543, 1544, 
    1545, 2258, 2257, 2256, 2255, 2260, 
    2259, 2251, 2265, 2264, 2263, 2253, 
    2363, 2364, 2365, 2373, 2374, 2559, 
    2560, 3663, 2587, 2588, 2589, 2590, 
    2603, 2609, 2610, 2611, 2696, 2697, 
    2695, 2694, 2723, 2724, 2725, 2726, 
    2729, 2730, 2731, 2732, 2742, 2743, 
    2744, 2745, 2746, 2747, 2749, 2750, 
    2751, 2752, 2753, 2754, 2755, 2756, 
    2757, 2761, 2762, 2763, 2764, 2822, 
    2823, 2824, 2825, 2826, 2842, 2843, 
    2844, 2845, 2846, 2847, 2854, 2855, 
    2856, 2857, 2858, 2859, 2927, 2928, 
    2929, 3026, 3030, 3029, 3090, 3091, 
    3092, 3093, 3094, 3096, 3097, 3098, 
    3136, 3137, 3138, 3140, 3141, 3142, 
    3610, 3556, 3557
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00382

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "250.66"
    },
    "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": 278,
            "rows_produced_per_join": 278,
            "filtered": "100.00",
            "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`cscart_products_categories`.`product_id` in (908,134,1142,853,1146,1145,1144,1143,856,1540,1541,1542,1543,1544,1545,2258,2257,2256,2255,2260,2259,2251,2265,2264,2263,2253,2363,2364,2365,2373,2374,2559,2560,3663,2587,2588,2589,2590,2603,2609,2610,2611,2696,2697,2695,2694,2723,2724,2725,2726,2729,2730,2731,2732,2742,2743,2744,2745,2746,2747,2749,2750,2751,2752,2753,2754,2755,2756,2757,2761,2762,2763,2764,2822,2823,2824,2825,2826,2842,2843,2844,2845,2846,2847,2854,2855,2856,2857,2858,2859,2927,2928,2929,3026,3030,3029,3090,3091,3092,3093,3094,3096,3097,3098,3136,3137,3138,3140,3141,3142,3610,3556,3557))",
            "cost_info": {
              "read_cost": "125.56",
              "eval_cost": "27.80",
              "prefix_cost": "153.36",
              "data_read_per_join": "4K"
            },
            "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": 13,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "69.50",
              "eval_cost": "1.39",
              "prefix_cost": "250.66",
              "data_read_per_join": "43K"
            },
            "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')))"
          }
        }
      ]
    }
  }
}