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 (
    99846, 99847, 99848, 99849, 99850, 99851, 
    99852, 99853, 99854, 99855, 99856, 
    99857, 99858, 99859, 99860, 99861, 
    99862, 99863, 99864, 99865, 99866, 
    99867, 99868, 99869, 99870, 99871, 
    99872, 99873, 99874, 99875, 99876, 
    99877, 99878, 99879, 99880, 99881, 
    99882, 99883, 99884, 99893, 99894, 
    99895, 99896, 99897, 99898, 99899, 
    99900, 99901, 99902, 99903, 99904, 
    99905, 99906, 99907, 99908, 99909, 
    99910, 99911, 99912, 99913, 99914, 
    99915, 99916, 99917, 99918, 99932, 
    99933, 99934, 99935, 99936, 99937, 
    99938, 99939, 99940, 99941, 99942, 
    99943, 99944, 99945, 99946, 99947, 
    99948, 99949, 99950, 99951, 99952, 
    99953, 99954, 99955, 99956, 99957, 
    99958, 99959, 99960, 99961, 99962
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00108

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 (99846,99847,99848,99849,99850,99851,99852,99853,99854,99855,99856,99857,99858,99859,99860,99861,99862,99863,99864,99865,99866,99867,99868,99869,99870,99871,99872,99873,99874,99875,99876,99877,99878,99879,99880,99881,99882,99883,99884,99893,99894,99895,99896,99897,99898,99899,99900,99901,99902,99903,99904,99905,99906,99907,99908,99909,99910,99911,99912,99913,99914,99915,99916,99917,99918,99932,99933,99934,99935,99936,99937,99938,99939,99940,99941,99942,99943,99944,99945,99946,99947,99948,99949,99950,99951,99952,99953,99954,99955,99956,99957,99958,99959,99960,99961,99962)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}