Sandbox

SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    2527, 11680, 2515, 2516, 2517, 2518, 
    15082, 2457, 2458, 2459, 2460, 2461, 
    2523, 2519, 2521, 2522
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": ["PRIMARY", "product_id"],
      "key": "product_id",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 16,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (2527,11680,2515,2516,2517,2518,15082,2457,2458,2459,2460,2461,2523,2519,2521,2522)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id	short_description	full_description
2457		<ul><li>Clear light to medium yellow colour with a small, fizzy, fair lacing, mostly diminishing, off-white head</li><li>Aroma is light to moderate malty, pale malt, sweet malt, corn, cardboard</li><li>Flavor is light to moderate sweet with a average duration, cardboard, cereal, sweet malt, corn</li><li>Body is light to medium, texture is watery, carbonation is soft</li><li>1 x case (24 x 330ML)</li></ul>
2458		<ul><li>Clear light to medium yellow colour with a small, fizzy, fair lacing, mostly diminishing, off-white head</li><li>Aroma is light to moderate malty, pale malt, sweet malt, corn, cardboard</li><li>Flavor is light to moderate sweet with a average duration, cardboard, cereal, sweet malt, corn</li><li>Body is light to medium, texture is watery, carbonation is soft</li><li>1 x case</li></ul> <p><br /></p>
2459		<ul><li>Clear light to medium yellow colour with a small, fizzy, fair lacing, mostly diminishing, off-white head</li><li>Aroma is light to moderate malty, pale malt, sweet malt, corn, cardboard</li><li>Flavor is light to moderate sweet with a average duration, cardboard, cereal, sweet malt, corn</li><li>Body is light to medium, texture is watery, carbonation is soft</li><li>1 x crate</li></ul>
2460		<ul><li>Clear light to medium yellow colour with a small, fizzy, fair lacing, mostly diminishing, off-white head</li><li>Aroma is light to moderate malty, pale malt, sweet malt, corn, cardboard</li><li>Flavor is light to moderate sweet with a average duration, cardboard, cereal, sweet malt, corn</li><li>Body is light to medium, texture is watery, carbonation is soft</li><li>1 x case (24 x340ML)</li></ul>
2461		<ul><li>True to the time-honored recipe, Stella Artois is crafted with three ingredients–<b>saaz hops, malted barley, and water</b></li><li>It has a wonderful hop aroma, well-balanced malt sweetness, crisp hop bitterness and a soft dry finish</li><li>It is the perfect beer to enjoy with food and friends</li><li>1 x case</li></ul>
2515		<ul><li>Sprite is a lemon-lime flavored soft drink with a crisp, clean taste that gives you the ultimate cut-through refreshment</li><li>1 case of 12</li></ul>
2516		<ul><li>Sprite is a lemon-lime flavored soft drink with a crisp, clean taste that gives you the ultimate cut-through refreshment</li><li>1 case of 6</li></ul>
2517		<ul><li>Sprite is a lemon-lime flavored soft drink with a crisp, clean taste that gives you the ultimate cut-through refreshment</li><li>1 case of 24 units</li></ul>
2518		<ul><li>Sprite is a lemon-lime flavored soft drink with a crisp, clean taste that gives you the ultimate cut-through refreshment</li><li>1 case of 24 units</li></ul>
2519		<ul><li>Stoney Ginger Beer is <b>a ginger-based soda</b>, with more kick than you're used to</li><li>On the stronger side of ginger sodas, Stoney Ginger Beer has a strong ginger bite that will keep you coming back for more</li><li>Called Stoney Tangawizi in Swahili speaking Africa, this ginger beer has changed how people think of soda</li><li>1 case of 12</li></ul>
2521		<ul><li>Stoney Ginger Beer is <b>a ginger-based soda</b>, with more kick than you're used to</li><li>On the stronger side of ginger sodas, Stoney Ginger Beer has a strong ginger bite that will keep you coming back for more</li><li>Called Stoney Tangawizi in Swahili speaking Africa, this ginger beer has changed how people think of soda</li><li>1 case of 6</li></ul>
2522		<ul><li>Stoney Ginger Beer is <b>a ginger-based soda</b>, with more kick than you're used to</li><li>On the stronger side of ginger sodas, Stoney Ginger Beer has a strong ginger bite that will keep you coming back for more</li><li>Called Stoney Tangawizi in Swahili speaking Africa, this ginger beer has changed how people think of soda</li><li>1 case of 24</li></ul>
2523		<ul><li>Stoney Ginger Beer is <b>a ginger-based soda</b>, with more kick than you're used to</li><li>On the stronger side of ginger sodas, Stoney Ginger Beer has a strong ginger bite that will keep you coming back for more</li><li>Called Stoney Tangawizi in Swahili speaking Africa, this ginger beer has changed how people think of soda</li><li>1 case of 6</li></ul><p><br /></p>
2527	<p>Source Water, Water</p>
11680		<p>Sprite 1.5L Case of 6</p>
15082