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 (
    155, 156, 157, 158, 159, 160, 161, 162, 
    163, 164, 165, 166, 167, 168, 169, 170
  ) 
  AND q_product_descriptions.lang_code = 'en'

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "38.41"
    },
    "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": 16,
      "rows_produced_per_join": 16,
      "filtered": "100.00",
      "index_condition": "((`portal`.`q_product_descriptions`.`product_id` in (155,156,157,158,159,160,161,162,163,164,165,166,167,168,169,170)) and (`portal`.`q_product_descriptions`.`lang_code` = 'en'))",
      "cost_info": {
        "read_cost": "35.21",
        "eval_cost": "3.20",
        "prefix_cost": "38.41",
        "data_read_per_join": "61K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ]
    }
  }
}

Result

product_id short_description full_description
155
156
157
158 <p>Jaguar Company, known for luxurious and visually appealing cars, expands their collection of perfumes with two brand new editions. These are fragrances for men Jaguar Classic Gold and Jaguar Classic Red available in characteristic flacons, as those of previous editions Jaguar, Classic Black and Classic Amber. The new flacons have the same form and accentuated the colors selected for the names of the new fragrances red and gold. </p>
159
160
161
162
163
164 <p>Pace by Jaguar is a Aromatic Fougere fragrance for men. Pace was launched in 2016. Pace was created by Alexandra Monet and Philippe Romano. Top notes are black pepper, green apple and rosemary; middle notes are cashmere wood, lavender and iris flower; base notes are amberwood, patchouli and moss.</p>
165
166
167
168
169
170