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 (
    2512, 2513, 3837, 3838, 3839, 6109, 6110, 
    2277, 2278, 2279, 2280, 2327, 2328, 
    2329, 2330, 2394, 2395, 2396, 2397, 
    2398, 2399, 2400, 2401, 2402, 2505, 
    2506, 2507, 2508, 5876, 5877, 5878, 
    5879, 5880, 5926, 5927, 5928, 5929, 
    5930, 5994, 5995, 5996, 5997, 5998, 
    5999, 6000, 6001, 6002, 6105, 6106, 
    6107, 6108, 1653, 2224, 1599, 1572, 
    2603, 6191, 2509, 1626, 2281, 2282, 
    2283, 2284, 2285, 2331, 2332, 2333, 
    2334, 2335, 2403, 2404, 2405, 2406, 
    2407, 2408, 2409, 2410, 2411, 2599, 
    2600, 2601, 2602, 5881, 5882, 5883, 
    5884, 5931, 5932, 5933, 5934, 6003, 
    6004, 6005, 6006, 6007, 6008
  )

Query time 0.00115

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "336.01"
    },
    "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": "(`test2_gaseus`.`p`.`product_id` in (2512,2513,3837,3838,3839,6109,6110,2277,2278,2279,2280,2327,2328,2329,2330,2394,2395,2396,2397,2398,2399,2400,2401,2402,2505,2506,2507,2508,5876,5877,5878,5879,5880,5926,5927,5928,5929,5930,5994,5995,5996,5997,5998,5999,6000,6001,6002,6105,6106,6107,6108,1653,2224,1599,1572,2603,6191,2509,1626,2281,2282,2283,2284,2285,2331,2332,2333,2334,2335,2403,2404,2405,2406,2407,2408,2409,2410,2411,2599,2600,2601,2602,5881,5882,5883,5884,5931,5932,5933,5934,6003,6004,6005,6006,6007,6008))",
          "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": [
            "test2_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": [
            "test2_gaseus.p.group_id"
          ],
          "rows_examined_per_scan": 7,
          "rows_produced_per_join": 672,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "168.00",
            "eval_cost": "67.20",
            "prefix_cost": "336.01",
            "data_read_per_join": "68K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}