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 (
    83049, 90885, 90964, 83070, 83623, 89816, 
    89868, 89940, 90906, 90985, 91506, 
    85848, 85849, 85858, 85859, 83081, 
    83609, 85081, 85167, 85213, 85259, 
    86142, 86165, 86658, 86727, 90920, 
    90999, 85854, 85855, 85864, 85865, 
    89997, 90004, 84535, 84601, 85121, 
    89077, 83074, 83075, 83627, 83628, 
    84657, 84658, 86627, 86696, 90910, 
    90911, 90989, 90990, 85084, 85085, 
    85170, 85171, 85216, 85217, 85262, 
    85263, 85314, 85411, 85462, 85513, 
    85317, 85318, 85414, 85415, 85465, 
    85466, 85516, 85517, 86471, 86472, 
    86747, 86748, 85838, 85839, 82852, 
    82853, 82925, 82926, 82998, 82999, 
    83514, 83515, 83522, 83523, 85844, 
    85845, 86192, 86215, 86524, 86800, 
    85124, 85125, 85363, 85364, 89075
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00191

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 (83049,90885,90964,83070,83623,89816,89868,89940,90906,90985,91506,85848,85849,85858,85859,83081,83609,85081,85167,85213,85259,86142,86165,86658,86727,90920,90999,85854,85855,85864,85865,89997,90004,84535,84601,85121,89077,83074,83075,83627,83628,84657,84658,86627,86696,90910,90911,90989,90990,85084,85085,85170,85171,85216,85217,85262,85263,85314,85411,85462,85513,85317,85318,85414,85415,85465,85466,85516,85517,86471,86472,86747,86748,85838,85839,82852,82853,82925,82926,82998,82999,83514,83515,83522,83523,85844,85845,86192,86215,86524,86800,85124,85125,85363,85364,89075)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}