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 (
    91342, 91348, 91335, 91340, 91332, 91361, 
    91363, 91391, 91393, 91362, 91364, 
    92240, 92245, 92247, 92248, 92249, 
    92250, 92252, 92253, 92485, 92486, 
    92487, 91392, 91394, 91359, 91389, 
    92508, 86828, 91331, 91360, 91357, 
    91387, 92241, 92242, 92243, 92244, 
    92246, 92251, 92483, 92484, 91358, 
    91390, 92488, 91388, 92476, 92477, 
    92478, 92479, 92480, 92481, 92482, 
    85554, 85570, 85543, 92239, 85591, 
    85597, 85600, 90755, 85556, 85557, 
    85589, 85593, 85601, 85602, 91320, 
    91322, 91324, 85587, 85588, 85604, 
    85562, 91318, 85542, 85603, 92475, 
    91319, 91321, 91323, 85547, 91317, 
    85568, 85544, 85558, 93282, 93284, 
    93286, 93288, 93290, 93294, 93338, 
    93339, 94428, 94750, 94759, 94760
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00072

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 (91342,91348,91335,91340,91332,91361,91363,91391,91393,91362,91364,92240,92245,92247,92248,92249,92250,92252,92253,92485,92486,92487,91392,91394,91359,91389,92508,86828,91331,91360,91357,91387,92241,92242,92243,92244,92246,92251,92483,92484,91358,91390,92488,91388,92476,92477,92478,92479,92480,92481,92482,85554,85570,85543,92239,85591,85597,85600,90755,85556,85557,85589,85593,85601,85602,91320,91322,91324,85587,85588,85604,85562,91318,85542,85603,92475,91319,91321,91323,85547,91317,85568,85544,85558,93282,93284,93286,93288,93290,93294,93338,93339,94428,94750,94759,94760)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}