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SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '', 
    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 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (6825, 6826, 6827) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00020

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": 3,
      "filtered": 100,
      "index_condition": "cscart_product_descriptions.product_id in (6825,6826,6827)",
      "attached_condition": "cscart_product_descriptions.lang_code = 'en'"
    }
  }
}

Result

product_id	short_description	full_description
6825		<p>The PMLN8298 provides wireless push-to-talk communication, an emergency button, and radio calling functions - volume control, PTT button, emergency/call button function. It requires PMLN8190, PMLN8077, or PMLN8125, earpiece.</p>
6826		<p>The vehicle mount can be easily mounted with the WP300 and attached to a steering wheel or other vehicle attachable locations. Includes hook and loop strap and cable tie.</p>
6827	<p>This kit includes the WP300 Wireless Bluetooth Control Pod and the translucent tube earpiece (PMLN8190).</p>