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 (
    32689, 32690, 32691, 32692, 32693, 32694, 
    32695, 32696, 32697, 32698, 32699, 
    32700, 32701, 32702, 32703, 32704, 
    32705, 32706, 32707, 32708, 32709, 
    32710, 32711, 32712, 32713, 32714, 
    32715, 32716, 32717, 32718, 32719, 
    32720
  ) 
  AND q_product_descriptions.lang_code = 'en'

Query time 0.00067

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 (32689,32690,32691,32692,32693,32694,32695,32696,32697,32698,32699,32700,32701,32702,32703,32704,32705,32706,32707,32708,32709,32710,32711,32712,32713,32714,32715,32716,32717,32718,32719,32720)) 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"
      ]
    }
  }
}