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 (
    3213, 3214, 3216, 3215, 3222, 3223, 3310, 
    3309, 3352, 3351, 3366, 3367, 3609, 
    3370, 3371, 3377, 3378, 3398, 3399, 
    3401, 3402, 3404, 3405, 3522, 3523, 
    3525, 3526, 3532, 3533, 3548, 3549, 
    3552, 3553, 3610, 3556, 3557, 3588, 
    3559, 3560, 3591, 3590, 3593, 3594, 
    3812, 3813, 3832, 3831, 3834, 3835, 
    3836, 3839, 3838, 3837, 3873, 3546, 
    3876, 3877, 3923, 3922, 3373, 4124, 
    4125
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00363

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "156.31"
    },
    "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": 176,
            "rows_produced_per_join": 176,
            "filtered": "100.00",
            "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`cscart_products_categories`.`product_id` in (3213,3214,3216,3215,3222,3223,3310,3309,3352,3351,3366,3367,3609,3370,3371,3377,3378,3398,3399,3401,3402,3404,3405,3522,3523,3525,3526,3532,3533,3548,3549,3552,3553,3610,3556,3557,3588,3559,3560,3591,3590,3593,3594,3812,3813,3832,3831,3834,3835,3836,3839,3838,3837,3873,3546,3876,3877,3923,3922,3373,4124,4125))",
            "cost_info": {
              "read_cost": "77.11",
              "eval_cost": "17.60",
              "prefix_cost": "94.71",
              "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": 8,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "44.00",
              "eval_cost": "0.88",
              "prefix_cost": "156.31",
              "data_read_per_join": "27K"
            },
            "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')))"
          }
        }
      ]
    }
  }
}