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 (
    98841, 98842, 98843, 98844, 98845, 98846, 
    98847, 98848, 98849, 98850, 98914, 
    98915, 98916, 98917, 98918, 98919, 
    98920, 98921, 98922, 98923, 98924, 
    98925, 98926, 98927, 98928, 98929, 
    98930, 98931, 98932, 98933, 98934, 
    98935, 98936, 98937, 98938, 98939, 
    98940, 98941, 98942, 98943, 98944, 
    98945, 98946, 98947, 98948, 98949, 
    98950, 98951, 98952, 98953, 98954, 
    98955, 98956, 98957, 98958, 98959, 
    98960, 98961, 98962, 98963, 98964, 
    98965, 98966, 98967, 98968, 98969, 
    98970, 98971, 98972, 98973, 98974, 
    98975, 98976, 98977, 98978, 98979, 
    98980, 98981, 98982, 98983, 98984, 
    98985, 98986, 98987, 98988, 98989, 
    98990, 98991, 98992, 98993, 98994, 
    98995, 98996, 98997, 98998, 98999
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00157

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 (98841,98842,98843,98844,98845,98846,98847,98848,98849,98850,98914,98915,98916,98917,98918,98919,98920,98921,98922,98923,98924,98925,98926,98927,98928,98929,98930,98931,98932,98933,98934,98935,98936,98937,98938,98939,98940,98941,98942,98943,98944,98945,98946,98947,98948,98949,98950,98951,98952,98953,98954,98955,98956,98957,98958,98959,98960,98961,98962,98963,98964,98965,98966,98967,98968,98969,98970,98971,98972,98973,98974,98975,98976,98977,98978,98979,98980,98981,98982,98983,98984,98985,98986,98987,98988,98989,98990,98991,98992,98993,98994,98995,98996,98997,98998,98999)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
98841
98842
98843
98844
98845
98846
98847
98848
98849
98850
98914
98915
98916
98917
98918
98919
98920
98921
98922
98923
98924
98925
98926
98927
98928
98929
98930
98931
98932
98933
98934
98935
98936
98937
98938
98939
98940
98941
98942
98943
98944
98945
98946
98947
98948
98949
98950
98951
98952
98953
98954
98955
98956
98957
98958
98959
98960
98961
98962
98963
98964
98965
98966
98967
98968
98969
98970
98971
98972
98973
98974
98975
98976
98977
98978
98979
98980
98981
98982
98983
98984
98985
98986
98987
98988
98989
98990
98991
98992
98993
98994
98995
98996
98997
98998
98999