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 (
    8501, 8503, 8504, 8506, 8507, 8508, 8509, 
    8510, 8511, 8512, 8514, 8515, 8516, 
    8517, 8518, 8519, 8521, 8477, 8476, 
    8474, 8377, 8376, 8375, 8374, 8368, 
    8367, 8272, 8271, 8270, 8269, 8268, 
    8267
  ) 
  AND q_product_descriptions.lang_code = 'en'

Query time 0.00068

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "76.81"
    },
    "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": 32,
      "rows_produced_per_join": 32,
      "filtered": "100.00",
      "index_condition": "((`portal`.`q_product_descriptions`.`product_id` in (8501,8503,8504,8506,8507,8508,8509,8510,8511,8512,8514,8515,8516,8517,8518,8519,8521,8477,8476,8474,8377,8376,8375,8374,8368,8367,8272,8271,8270,8269,8268,8267)) and (`portal`.`q_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "70.41",
        "eval_cost": "6.40",
        "prefix_cost": "76.81",
        "data_read_per_join": "122K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ]
    }
  }
}