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SELECT 
  cscart_product_review_prepared_data.product_id AS product_id, 
  cscart_product_review_prepared_data.average_rating AS average_rating, 
  cscart_product_review_prepared_data.reviews_count AS reviews_count 
FROM 
  cscart_product_review_prepared_data 
WHERE 
  cscart_product_review_prepared_data.product_id IN (
    51509, 51515, 51466, 51485, 51518, 51550, 
    51519, 51524, 51528, 51508, 51527, 
    51543, 51482, 51504, 51542, 51512
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 1

Query time 0.00027

JSON explain

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