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 (
    88015, 87972, 88091, 88055, 88085, 88703, 
    88750, 87809, 87811, 87814, 87817, 
    87824, 90327, 88071, 88076, 88090, 
    87944, 88595, 88072, 88154, 87808, 
    87810, 87813, 87816, 87823, 87874, 
    87779, 87783, 87793, 87799, 87880, 
    87873, 90317, 90319, 90320, 88087, 
    88797, 87960, 87778, 87782, 87791, 
    87797, 87760, 88701, 88748, 88596, 
    88030, 88086
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00095

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.62"
    },
    "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": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "16.82",
        "eval_cost": "4.80",
        "prefix_cost": "21.62",
        "data_read_per_join": "183K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (88015,87972,88091,88055,88085,88703,88750,87809,87811,87814,87817,87824,90327,88071,88076,88090,87944,88595,88072,88154,87808,87810,87813,87816,87823,87874,87779,87783,87793,87799,87880,87873,90317,90319,90320,88087,88797,87960,87778,87782,87791,87797,87760,88701,88748,88596,88030,88086)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}