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 (
    98793, 98794, 98795, 98796, 98797, 98798, 
    98799, 98800, 98801, 98802, 98803, 
    98804, 98805, 98806, 98807, 98808, 
    98809, 98810, 98811, 98812, 98813, 
    98814, 98831, 98832, 98833, 98834, 
    98835, 98836, 98837, 98838, 98839, 
    98840, 98841, 98842, 98843, 98844, 
    98845, 98846, 98847, 98848, 98849, 
    98850, 98851, 98852, 98853, 98854, 
    98855, 98856, 98857, 98858, 98874, 
    98875, 98876, 98877, 98897, 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
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00158

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "53.72"
    },
    "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": "44.13",
        "eval_cost": "9.60",
        "prefix_cost": "53.73",
        "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 (98793,98794,98795,98796,98797,98798,98799,98800,98801,98802,98803,98804,98805,98806,98807,98808,98809,98810,98811,98812,98813,98814,98831,98832,98833,98834,98835,98836,98837,98838,98839,98840,98841,98842,98843,98844,98845,98846,98847,98848,98849,98850,98851,98852,98853,98854,98855,98856,98857,98858,98874,98875,98876,98877,98897,98914,98915,98916,98917,98918,98919,98920,98921,98922,98923,98924,98925,98926,98927,98928,98929,98930,98931,98932,98933,98934,98935,98936,98937,98938,98939,98940,98941,98942,98943,98944,98945,98946,98947,98948,98949,98950,98951,98952,98953,98954)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
98793
98794
98795
98796
98797
98798
98799
98800
98801
98802
98803
98804
98805
98806
98807
98808
98809
98810
98811
98812
98813
98814
98831
98832
98833
98834
98835
98836
98837
98838
98839
98840
98841
98842
98843
98844
98845
98846
98847
98848
98849
98850
98851
98852
98853
98854
98855
98856
98857
98858
98874
98875
98876
98877
98897
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