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 (
    98356, 98357, 98358, 98359, 98360, 98361, 
    98362, 98363, 98364, 98365, 98366, 
    98367, 98368, 98369, 98370, 98371, 
    98372, 98373, 98374, 98375, 98376, 
    98377, 98378, 98379, 98380, 98381, 
    98382, 98383, 98384, 98385, 98386, 
    98387, 98388, 98389, 98390, 98391, 
    98392, 98393, 98394, 98395, 98396, 
    98397, 98398, 98399, 98400, 98401, 
    98402, 98403
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00103

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.63"
    },
    "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": "16.83",
        "eval_cost": "4.80",
        "prefix_cost": "21.63",
        "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 (98356,98357,98358,98359,98360,98361,98362,98363,98364,98365,98366,98367,98368,98369,98370,98371,98372,98373,98374,98375,98376,98377,98378,98379,98380,98381,98382,98383,98384,98385,98386,98387,98388,98389,98390,98391,98392,98393,98394,98395,98396,98397,98398,98399,98400,98401,98402,98403)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}