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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 (
    51491, 51492, 51513, 51474, 51515, 51502, 
    51518, 51466, 51512, 51465, 51482, 
    51485, 51511, 51528, 51527, 51505, 
    51493, 51535
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 1

Query time 0.00021

JSON explain

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