SELECT 
  product_descriptions.product_id, 
  product_descriptions.short_description, 
  IF(
    product_descriptions.short_description = '' 
    OR product_descriptions.short_description IS NULL, 
    product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  product_descriptions 
WHERE 
  product_descriptions.product_id IN (
    385788, 385792, 386515, 386529, 386536, 
    386546, 386549, 387058, 387081, 387083, 
    387085, 387120, 387867, 388404, 389711, 
    389713, 389714, 389715, 389730, 390516, 
    390517, 391044, 391788, 391796
  ) 
  AND product_descriptions.lang_code = 'en'

Query time 0.00152

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "20.40"
    },
    "table": {
      "table_name": "product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "11",
      "rows_examined_per_scan": 24,
      "rows_produced_per_join": 24,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "18.00",
        "eval_cost": "2.40",
        "prefix_cost": "20.40",
        "data_read_per_join": "122K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`goimagine`.`product_descriptions`.`product_id` in (385788,385792,386515,386529,386536,386546,386549,387058,387081,387083,387085,387120,387867,388404,389711,389713,389714,389715,389730,390516,390517,391044,391788,391796)) and (`goimagine`.`product_descriptions`.`lang_code` = 'en'))"
    }
  }
}