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 (
    85494, 85496, 84308, 84309, 84519, 84585, 
    89054, 84331, 84332, 85341, 85343, 
    86903, 86928, 86964, 86989, 87025, 
    87050, 87108, 90796, 83289, 83291, 
    83296, 83298, 90565, 90566, 90571, 
    90572, 90577, 90578, 91395, 91397, 
    91399, 91401, 91403, 91405, 91407, 
    91409, 91411, 91413, 91415, 91417, 
    84304, 84305, 84632, 84633, 83303, 
    83305, 90553, 90554, 91100, 91101, 
    91104, 91105, 91107, 91108, 91109, 
    91186, 91187, 91190, 91191, 91193, 
    91194, 91195, 91241, 91242, 91245, 
    91246, 91248, 91249, 91250, 89755, 
    89757, 86187, 86210, 86511, 86787, 
    84681, 84682, 84685, 84686, 91076, 
    91077, 91080, 91081, 91083, 91084, 
    91085, 86902, 86927, 86963, 86988, 
    87024, 87049, 87085, 87107, 91131
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00186

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 (85494,85496,84308,84309,84519,84585,89054,84331,84332,85341,85343,86903,86928,86964,86989,87025,87050,87108,90796,83289,83291,83296,83298,90565,90566,90571,90572,90577,90578,91395,91397,91399,91401,91403,91405,91407,91409,91411,91413,91415,91417,84304,84305,84632,84633,83303,83305,90553,90554,91100,91101,91104,91105,91107,91108,91109,91186,91187,91190,91191,91193,91194,91195,91241,91242,91245,91246,91248,91249,91250,89755,89757,86187,86210,86511,86787,84681,84682,84685,84686,91076,91077,91080,91081,91083,91084,91085,86902,86927,86963,86988,87024,87049,87085,87107,91131)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}