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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 (
    827, 826, 595, 485, 486, 838, 549, 660, 
    546, 1260, 978, 979, 401, 400, 457, 462, 
    516, 564, 321, 989, 987, 988, 748, 502
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 0

Query time 0.00046

JSON explain

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