SELECT 
  cscart_product_feature_variant_descriptions.variant, 
  cscart_product_feature_variants.variant_id, 
  cscart_product_feature_variants.feature_id, 
  cscart_product_features_values.variant_id as selected, 
  cscart_product_features.feature_type, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path, 
  cscart_product_feature_variants.mdc_variant 
FROM 
  cscart_product_feature_variants 
  LEFT JOIN cscart_product_feature_variant_descriptions ON cscart_product_feature_variant_descriptions.variant_id = cscart_product_feature_variants.variant_id 
  AND cscart_product_feature_variant_descriptions.lang_code = 'en' 
  INNER JOIN cscart_product_features_values ON cscart_product_features_values.variant_id = cscart_product_feature_variants.variant_id 
  AND cscart_product_features_values.lang_code = 'en' 
  AND cscart_product_features_values.product_id = 345 
  AND cscart_product_features_values.feature_id = cscart_product_feature_variants.feature_id 
  LEFT JOIN cscart_product_features ON cscart_product_features.feature_id = cscart_product_feature_variants.feature_id 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = cscart_product_feature_variants.variant_id 
  AND cscart_seo_names.type = 'e' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'en' 
WHERE 
  1 
  AND cscart_product_feature_variants.feature_id IN (
    1055, 1151, 1080, 1152, 1041, 1057, 1046, 
    1050, 1072, 1059, 1047, 1073, 1074, 
    1071, 1140, 1067, 1061, 1064, 1065, 
    1044, 1069, 1076, 1078, 1079, 1135, 
    1056, 1052, 1063, 1141, 1070, 1042, 
    1077, 1066, 1054, 1084, 1136, 1062, 
    1043, 1053, 1075, 1083, 1060, 1068, 
    1085, 1081, 1082, 1086, 1045
  ) 
GROUP BY 
  cscart_product_feature_variants.variant_id 
ORDER BY 
  cscart_product_feature_variants.position, 
  cscart_product_feature_variant_descriptions.variant

Query time 0.00463

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "53.29"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": false,
        "nested_loop": [
          {
            "table": {
              "table_name": "cscart_product_features_values",
              "access_type": "ref",
              "possible_keys": [
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                "lang_code",
                "product_id",
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                "idx_product_feature_variant_id"
              ],
              "key": "idx_product_feature_variant_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "const"
              ],
              "rows_examined_per_scan": 11,
              "rows_produced_per_join": 5,
              "filtered": "53.56",
              "using_index": true,
              "cost_info": {
                "read_cost": "1.40",
                "eval_cost": "1.18",
                "prefix_cost": "3.60",
                "data_read_per_join": "4K"
              },
              "used_columns": [
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                "variant_id",
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              ],
              "attached_condition": "((`danishecarter_25_march`.`cscart_product_features_values`.`feature_id` in (1055,1151,1080,1152,1041,1057,1046,1050,1072,1059,1047,1073,1074,1071,1140,1067,1061,1064,1065,1044,1069,1076,1078,1079,1135,1056,1052,1063,1141,1070,1042,1077,1066,1054,1084,1136,1062,1043,1053,1075,1083,1060,1068,1085,1081,1082,1086,1045)) and (`danishecarter_25_march`.`cscart_product_features_values`.`lang_code` = 'en'))"
            }
          },
          {
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              ],
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            }
          },
          {
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              "used_columns": [
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              ]
            }
          },
          {
            "table": {
              "table_name": "cscart_product_feature_variant_descriptions",
              "access_type": "eq_ref",
              "possible_keys": [
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              "key": "PRIMARY",
              "used_key_parts": [
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                "lang_code"
              ],
              "key_length": "9",
              "ref": [
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              },
              "used_columns": [
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              ]
            }
          },
          {
            "table": {
              "table_name": "cscart_seo_names",
              "access_type": "ref",
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                "dispatch"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
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              "key_length": "206",
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              ],
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              "used_columns": [
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                "object_id",
                "type",
                "dispatch",
                "path",
                "lang_code"
              ]
            }
          }
        ]
      }
    }
  }
}