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 (
    97320, 97321, 97322, 97323, 97324, 97325, 
    97326, 97327, 97328, 97329, 97330, 
    97331, 97332, 97333, 97334, 97335, 
    97336, 97337, 97338, 97339, 97340, 
    97341, 97342, 97343, 97344, 97345, 
    97346, 97347, 97348, 97349, 97350, 
    97351, 97352, 97353, 97354, 97355, 
    97356, 97357, 97358, 97359, 97360, 
    97361, 97362, 97363, 97364, 97365, 
    97366, 97367
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00089

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 (97320,97321,97322,97323,97324,97325,97326,97327,97328,97329,97330,97331,97332,97333,97334,97335,97336,97337,97338,97339,97340,97341,97342,97343,97344,97345,97346,97347,97348,97349,97350,97351,97352,97353,97354,97355,97356,97357,97358,97359,97360,97361,97362,97363,97364,97365,97366,97367)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}