SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    96453, 96454, 96455, 96456, 96457, 96458, 
    96459, 96460, 96461, 96462, 96463, 
    96464, 96465, 96466, 96467, 96468, 
    96469, 96470, 96471, 96472, 96473, 
    96474, 98602, 98606, 98608, 98610, 
    98625, 98627, 98629, 98634, 98636, 
    98638, 98642, 98643, 98648, 98654, 
    98655, 98656, 98660, 98662, 98664, 
    98670, 99704, 99705, 99717, 99718, 
    99720, 99839, 99840, 99841, 99842, 
    99844, 99847, 99849, 99851, 99854, 
    99856, 99858, 99859, 99861, 99863, 
    99864, 99866, 99868, 99870, 99871, 
    99873, 99876, 99878, 99881, 99883, 
    99893, 99894, 99897, 99898, 99901, 
    99902, 99905, 99906, 99909, 99910, 
    99913, 99914, 99917, 99918, 99932, 
    99934, 99938, 99940, 99942, 99948, 
    99950, 99956, 99958, 99962, 99964
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00084

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.24"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 96,
      "rows_produced_per_join": 96,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "33.64",
        "eval_cost": "9.60",
        "prefix_cost": "43.24",
        "data_read_per_join": "366K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (96453,96454,96455,96456,96457,96458,96459,96460,96461,96462,96463,96464,96465,96466,96467,96468,96469,96470,96471,96472,96473,96474,98602,98606,98608,98610,98625,98627,98629,98634,98636,98638,98642,98643,98648,98654,98655,98656,98660,98662,98664,98670,99704,99705,99717,99718,99720,99839,99840,99841,99842,99844,99847,99849,99851,99854,99856,99858,99859,99861,99863,99864,99866,99868,99870,99871,99873,99876,99878,99881,99883,99893,99894,99897,99898,99901,99902,99905,99906,99909,99910,99913,99914,99917,99918,99932,99934,99938,99940,99942,99948,99950,99956,99958,99962,99964)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
96453
96454
96455
96456
96457
96458
96459
96460
96461
96462
96463
96464
96465
96466
96467
96468
96469
96470
96471
96472
96473
96474
98602
98606
98608
98610
98625
98627
98629
98634
98636
98638
98642
98643
98648
98654
98655
98656
98660
98662
98664
98670
99704
99705
99717
99718
99720
99839
99840
99841
99842
99844
99847
99849
99851
99854
99856
99858
99859
99861
99863
99864
99866
99868
99870
99871
99873
99876
99878
99881
99883
99893
99894
99897
99898
99901
99902
99905
99906
99909
99910
99913
99914
99917
99918
99932
99934
99938
99940
99942
99948
99950
99956
99958
99962
99964