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 (
    2603, 3136, 2587, 2761, 2694, 3096, 2723, 
    2742, 3556, 2593, 3104, 2618, 2828, 
    2613, 2619, 2872, 2704, 3593, 4888, 
    3423, 5168, 2739, 3291, 5998, 2841, 
    5155, 3876, 2561, 3812, 5124, 6007, 
    2865, 2734, 3369, 6005, 6019, 3139, 
    5157, 2700, 5121, 5929, 2701, 6013, 
    2797, 6271, 5938, 5980, 4886, 4885, 
    8243, 5933, 6006, 5981, 6024, 5983, 
    8603, 10022, 8272, 7878, 8879, 7880, 
    8458
  )

Query time 0.00193

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "92.56"
    },
    "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": 67,
          "rows_produced_per_join": 67,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`p`.`product_id` in (2603,3136,2587,2761,2694,3096,2723,2742,3556,2593,3104,2618,2828,2613,2619,2872,2704,3593,4888,3423,5168,2739,3291,5998,2841,5155,3876,2561,3812,5124,6007,2865,2734,3369,6005,6019,3139,5157,2700,5121,5929,2701,6013,2797,6271,5938,5980,4886,4885,8243,5933,6006,5981,6024,5983,8603,10022,8272,7878,8879,7880,8458))",
          "cost_info": {
            "read_cost": "38.96",
            "eval_cost": "6.70",
            "prefix_cost": "45.66",
            "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": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 67,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "16.75",
            "eval_cost": "6.70",
            "prefix_cost": "69.11",
            "data_read_per_join": "26K"
          },
          "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": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 67,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "16.75",
            "eval_cost": "6.70",
            "prefix_cost": "92.56",
            "data_read_per_join": "6K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}