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 (
    96121, 96494, 96495, 96496, 96497, 96498, 
    96499, 96500, 96501, 96502, 96503, 
    96504, 96505, 96506, 96507, 96508, 
    96509, 96530, 96570, 96571, 96572, 
    96573, 97574, 97575, 97581, 97608, 
    97609, 97610, 97611, 97612, 97613, 
    97614, 97615, 97616, 97617, 97618, 
    97619, 97620, 97621, 97622, 97623, 
    97624, 97625, 97626, 97627, 97629, 
    97630, 97631, 97632, 97633, 97634, 
    97635, 97636, 97637, 97638, 97639, 
    97640, 97641, 97642, 97643, 97644, 
    97645, 97646, 97647, 97648, 97649, 
    97650, 97651, 97652, 97653, 97654, 
    97655, 97656, 97657, 97658, 97659, 
    97660, 97661, 97662, 97663, 97664, 
    97665, 97666, 97667, 97668, 97669, 
    97670, 97671, 97672, 97673, 97674, 
    97675, 97676, 97677, 97678, 97679
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00138

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 (96121,96494,96495,96496,96497,96498,96499,96500,96501,96502,96503,96504,96505,96506,96507,96508,96509,96530,96570,96571,96572,96573,97574,97575,97581,97608,97609,97610,97611,97612,97613,97614,97615,97616,97617,97618,97619,97620,97621,97622,97623,97624,97625,97626,97627,97629,97630,97631,97632,97633,97634,97635,97636,97637,97638,97639,97640,97641,97642,97643,97644,97645,97646,97647,97648,97649,97650,97651,97652,97653,97654,97655,97656,97657,97658,97659,97660,97661,97662,97663,97664,97665,97666,97667,97668,97669,97670,97671,97672,97673,97674,97675,97676,97677,97678,97679)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}

Result

product_id short_description full_description
96121
96494
96495
96496
96497
96498
96499
96500
96501
96502
96503
96504
96505
96506
96507
96508
96509
96530
96570
96571
96572
96573
97574
97575
97581
97608
97609
97610
97611
97612
97613
97614
97615
97616
97617
97618
97619
97620
97621
97622
97623
97624
97625
97626
97627
97629
97630
97631
97632
97633
97634
97635
97636
97637
97638
97639
97640
97641
97642
97643
97644
97645
97646
97647
97648
97649
97650
97651
97652
97653
97654
97655
97656
97657
97658
97659
97660
97661
97662
97663
97664
97665
97666
97667
97668
97669
97670
97671
97672
97673
97674
97675
97676
97677
97678
97679