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 (
    96762, 96763, 96764, 96765, 96766, 96771, 
    96772, 96775, 96776, 96777, 96985, 
    96986, 96987, 96988, 96989, 96990, 
    96991, 96992, 96993, 96994, 96995, 
    96996, 96997, 96999, 97000, 97001, 
    97002, 97003, 97004, 97005, 97006, 
    97007, 97008, 97009, 97010, 97820, 
    97821, 97829, 97830, 97831, 97832, 
    98039, 98258, 98259, 98260, 98261, 
    98262, 98263, 98264, 98265, 98274, 
    98275, 98276, 98277, 98278, 98279, 
    98280, 98281, 98282, 98283, 98284, 
    98285, 98286, 98287, 98288, 98289, 
    98290, 98291, 98292, 98293, 98294, 
    98295, 98296, 98297, 98298, 98299, 
    98300, 98301, 98302, 98303, 98304, 
    98305, 98306, 98307, 98308, 98309, 
    98310, 98311, 98312, 98313, 98314, 
    98315, 98316, 98317, 98318, 98319
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00133

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 (96762,96763,96764,96765,96766,96771,96772,96775,96776,96777,96985,96986,96987,96988,96989,96990,96991,96992,96993,96994,96995,96996,96997,96999,97000,97001,97002,97003,97004,97005,97006,97007,97008,97009,97010,97820,97821,97829,97830,97831,97832,98039,98258,98259,98260,98261,98262,98263,98264,98265,98274,98275,98276,98277,98278,98279,98280,98281,98282,98283,98284,98285,98286,98287,98288,98289,98290,98291,98292,98293,98294,98295,98296,98297,98298,98299,98300,98301,98302,98303,98304,98305,98306,98307,98308,98309,98310,98311,98312,98313,98314,98315,98316,98317,98318,98319)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
96762
96763
96764
96765
96766
96771
96772
96775
96776
96777
96985
96986
96987
96988
96989
96990
96991
96992
96993
96994
96995
96996
96997
96999
97000
97001
97002
97003
97004
97005
97006
97007
97008
97009
97010
97820
97821
97829
97830
97831
97832
98039
98258
98259
98260
98261
98262
98263
98264
98265
98274
98275
98276
98277
98278
98279
98280
98281
98282
98283
98284
98285
98286
98287
98288
98289
98290
98291
98292
98293
98294
98295
98296
98297
98298
98299
98300
98301
98302
98303
98304
98305
98306
98307
98308
98309
98310
98311
98312
98313
98314
98315
98316
98317
98318
98319