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 = 7165 
WHERE 
  cscart_products_categories.product_id IN (
    93920, 93921, 93922, 93923, 93924, 93925, 
    93926, 93927, 93928, 93929, 93930, 
    93931, 93932, 93933, 93934, 93935, 
    93936, 93937, 93938, 93939, 93940, 
    93941, 93942, 93943, 93944, 93945, 
    93946, 93947, 93948, 93949, 93950, 
    93951, 93952, 93953, 93954, 93955, 
    93956, 93957, 93958, 93959, 93960, 
    93961, 93962, 93963, 93964, 93965, 
    93966, 93967, 93968, 93969, 93970, 
    93971, 93972, 93973, 93974, 93975, 
    93976, 93977, 93978, 93979, 93980, 
    93981, 93982, 93983, 93984, 93985, 
    93986, 93987, 93988, 93989, 93990, 
    93991, 93992, 93993, 93994, 93995, 
    93996, 93997, 93998, 93999, 94000, 
    94001, 94002, 94003, 94004, 94005, 
    94006, 94007, 94008, 94009, 94010, 
    94011, 94012, 94013, 94014, 94015
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.01560

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "86.69"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "link_type",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 96,
            "rows_produced_per_join": 96,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.89",
              "eval_cost": "9.60",
              "prefix_cost": "19.49",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (93920,93921,93922,93923,93924,93925,93926,93927,93928,93929,93930,93931,93932,93933,93934,93935,93936,93937,93938,93939,93940,93941,93942,93943,93944,93945,93946,93947,93948,93949,93950,93951,93952,93953,93954,93955,93956,93957,93958,93959,93960,93961,93962,93963,93964,93965,93966,93967,93968,93969,93970,93971,93972,93973,93974,93975,93976,93977,93978,93979,93980,93981,93982,93983,93984,93985,93986,93987,93988,93989,93990,93991,93992,93993,93994,93995,93996,93997,93998,93999,94000,94001,94002,94003,94004,94005,94006,94007,94008,94009,94010,94011,94012,94013,94014,94015))"
          }
        },
        {
          "table": {
            "table_name": "product_position_source",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id",
              "product_id"
            ],
            "key_length": "6",
            "ref": [
              "const",
              "nuie_scalesta_net.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 96,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "24.00",
              "eval_cost": "9.60",
              "prefix_cost": "53.09",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "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": [
              "nuie_scalesta_net.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 4,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "24.00",
              "eval_cost": "0.48",
              "prefix_cost": "86.69",
              "data_read_per_join": "12K"
            },
            "used_columns": [
              "category_id",
              "usergroup_ids",
              "status",
              "storefront_id"
            ],
            "attached_condition": "((`nuie_scalesta_net`.`cscart_categories`.`storefront_id` in (0,1)) and ((`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`))) and (`nuie_scalesta_net`.`cscart_categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}