SELECT 
  q_product_descriptions.product_id, 
  q_product_descriptions.short_description, 
  IF(
    q_product_descriptions.short_description = '', 
    q_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  q_product_descriptions 
WHERE 
  q_product_descriptions.product_id IN (
    31047, 31053, 31068, 31074, 31082, 31089, 
    31091, 31117, 31129, 31151, 31155, 
    31156, 10422, 10429, 10431, 10432, 
    10433, 10027, 10028, 4579, 4580, 3352, 
    3353
  ) 
  AND q_product_descriptions.lang_code = 'en'

Query time 0.00063

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "55.21"
    },
    "table": {
      "table_name": "q_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": 23,
      "rows_produced_per_join": 23,
      "filtered": "100.00",
      "index_condition": "((`portal`.`q_product_descriptions`.`product_id` in (31047,31053,31068,31074,31082,31089,31091,31117,31129,31151,31155,31156,10422,10429,10431,10432,10433,10027,10028,4579,4580,3352,3353)) and (`portal`.`q_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "50.61",
        "eval_cost": "4.60",
        "prefix_cost": "55.21",
        "data_read_per_join": "87K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ]
    }
  }
}