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SELECT 
  cscart_ult_product_descriptions.product_id, 
  cscart_ult_product_descriptions.short_description, 
  IF(
    cscart_ult_product_descriptions.short_description = "", 
    cscart_ult_product_descriptions.full_description, 
    ""
  ) AS full_description, 
  cscart_ult_product_descriptions.meta_keywords, 
  cscart_ult_product_descriptions.meta_description, 
  cscart_ult_product_descriptions.search_words, 
  cscart_ult_product_descriptions.promo_text 
FROM 
  cscart_ult_product_descriptions 
WHERE 
  cscart_ult_product_descriptions.product_id IN (
    12551, 12544, 12546, 12547, 12548, 12549, 
    12550, 12555, 12556, 12557, 12558, 
    12559, 12576, 12577, 12578, 9683, 9685, 
    9686, 9687, 9688, 9689, 9690, 12560, 
    12561, 9775, 9776, 9777, 9778, 9779, 
    9780, 9781, 9782, 9783, 9784, 9785, 
    9786, 9787, 9788, 9790, 9791, 9792, 
    9795, 9797, 9798, 9799, 9800, 9801, 
    9802, 9803, 9804, 9805, 9806, 9807, 
    9808, 9809, 9810, 9811, 9812, 9814, 
    9815, 9816, 9817, 9818, 9820
  ) 
  AND cscart_ult_product_descriptions.company_id = 1 
  AND cscart_ult_product_descriptions.lang_code = 'ru'

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}