SELECT 
  f.feature_id, 
  f.purpose, 
  p.product_id, 
  p.parent_product_id, 
  g.id, 
  g.code 
FROM 
  cscart_product_variation_group_features AS f 
  INNER JOIN cscart_product_variation_groups AS g ON f.group_id = g.id 
  INNER JOIN cscart_product_variation_group_products AS p ON f.group_id = p.group_id 
WHERE 
  p.product_id IN (
    2271, 2336, 2337, 2338, 2339, 2412, 2413, 
    2414, 2415, 2416, 2417, 2418, 2419, 
    2420, 2514, 2515, 2516, 2517, 2518, 
    2604, 2605, 2606, 2607, 3840, 3841, 
    3842, 3843, 5867, 5868, 5869, 5870, 
    5871, 5935, 5936, 5937, 5938, 5939, 
    6012, 6013, 6014, 6015, 6016, 6017, 
    6018, 6019, 6020, 6196, 6197, 6198, 
    6199, 6200, 6732, 2836, 2837, 2838, 
    2839, 2840, 6422, 6423, 6424, 6425, 
    2937, 2938, 2939, 2940, 2941, 6522, 
    6523, 6524, 6525, 2189, 2190, 2191, 
    2192, 2193, 2194, 2195, 2196, 2197, 
    2720, 2721, 2722, 2723, 2769, 2770, 
    2771, 2772, 2773, 2774, 2775, 2776, 
    2777, 2845, 2846, 2847, 2848
  )

Query time 0.00114

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "201.61"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "p",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "product_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 96,
          "rows_produced_per_join": 96,
          "filtered": "100.00",
          "index_condition": "(`gaseus`.`p`.`product_id` in (2271,2336,2337,2338,2339,2412,2413,2414,2415,2416,2417,2418,2419,2420,2514,2515,2516,2517,2518,2604,2605,2606,2607,3840,3841,3842,3843,5867,5868,5869,5870,5871,5935,5936,5937,5938,5939,6012,6013,6014,6015,6016,6017,6018,6019,6020,6196,6197,6198,6199,6200,6732,2836,2837,2838,2839,2840,6422,6423,6424,6425,2937,2938,2939,2940,2941,6522,6523,6524,6525,2189,2190,2191,2192,2193,2194,2195,2196,2197,2720,2721,2722,2723,2769,2770,2771,2772,2773,2774,2775,2776,2777,2845,2846,2847,2848))",
          "cost_info": {
            "read_cost": "57.61",
            "eval_cost": "9.60",
            "prefix_cost": "67.21",
            "data_read_per_join": "1K"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "id"
          ],
          "key_length": "3",
          "ref": [
            "gaseus.p.group_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": "100.81",
            "data_read_per_join": "37K"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "f",
          "access_type": "ref",
          "possible_keys": [
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "gaseus.p.group_id"
          ],
          "rows_examined_per_scan": 3,
          "rows_produced_per_join": 288,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "72.00",
            "eval_cost": "28.80",
            "prefix_cost": "201.61",
            "data_read_per_join": "29K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}