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 (
    5676, 5808, 5247, 5555, 5580, 5371, 4135, 
    5575, 5392, 6368, 5573, 5915, 5540, 
    5466, 4755, 5570, 5260, 5642, 5108, 
    5110, 5390, 5576, 5023, 5203, 5256, 
    5569, 5616, 5257, 4647, 4649, 4661, 
    5180, 5200, 4762, 5118, 5372, 5106, 
    5258, 4648, 4459
  )

Query time 0.00063

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "56.01"
    },
    "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": 40,
          "rows_produced_per_join": 40,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`p`.`product_id` in (5676,5808,5247,5555,5580,5371,4135,5575,5392,6368,5573,5915,5540,5466,4755,5570,5260,5642,5108,5110,5390,5576,5023,5203,5256,5569,5616,5257,4647,4649,4661,5180,5200,4762,5118,5372,5106,5258,4648,4459))",
          "cost_info": {
            "read_cost": "24.01",
            "eval_cost": "4.00",
            "prefix_cost": "28.01",
            "data_read_per_join": "640"
          },
          "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": 40,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "10.00",
            "eval_cost": "4.00",
            "prefix_cost": "42.01",
            "data_read_per_join": "15K"
          },
          "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": 40,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "10.00",
            "eval_cost": "4.00",
            "prefix_cost": "56.01",
            "data_read_per_join": "4K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}