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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, 
  cscart_product_descriptions.meta_keywords, 
  cscart_product_descriptions.meta_description, 
  cscart_product_descriptions.search_words, 
  cscart_product_descriptions.promo_text, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (41, 28, 27) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00025

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	cscart_product_descriptions	range	PRIMARY,product_id	PRIMARY	9		3	Using index condition

Result

product_id	short_description	full_description	promo_text
27	<p>This classic women's adidas Originals Trefoil Logo Hoodie is made of comfortable fleece with a drawcord hood, a kangaroo pocket and an outsize logo. The pullover hoodie also features extra-long cuffs and hem for feminine style.</p>		<p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>
28		<p>adidas Run Perf 7/8 Ti , new to site, more details coming soon.</p>	<p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>
41		<p>Welcome the new addition with this adidas Originals Gift Set, featuring a one-piece romper and matching socks. The romper has a sleepy-time Trefoil character on the back, while the front bristles with fun in vibrant stripes.</p><div class="prodDetail"><h3>Details</h3><ul><li>Crewneck</li><li>Full snap-button front for easy on and off</li><li>Allover yarn-dyed stripe pattern on front</li><li>Solid-color back with Trefoil-inspired graphic</li><li>Matching socks included</li><li>95% cotton / 5% elastane single jersey</li><li>Imported</li></ul></div>	<p class="product-promo-text"><span class="product-promo-header">FREE US shipping over $100!</span><span class="product-promo-body">Orders within next 2 days will be shipped on Monday</span></p>