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 (
    99342, 99343, 99404, 99405, 99406, 99407, 
    99408, 99409, 99410, 99411, 99422, 
    99423, 99424, 99425, 99426, 99427, 
    99428, 99429, 99430, 99431, 99432, 
    99433, 99434, 99435, 99436, 99437, 
    99491, 99492, 99493, 99494, 99495, 
    99496, 99497, 99498, 99499, 99500, 
    99501, 99502, 99503, 99504, 99505, 
    99506, 99508, 99509, 99510, 99512, 
    99513, 99514
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00096

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 (99342,99343,99404,99405,99406,99407,99408,99409,99410,99411,99422,99423,99424,99425,99426,99427,99428,99429,99430,99431,99432,99433,99434,99435,99436,99437,99491,99492,99493,99494,99495,99496,99497,99498,99499,99500,99501,99502,99503,99504,99505,99506,99508,99509,99510,99512,99513,99514)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}