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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 (
    21088, 20980, 21071, 21074, 21072, 21073, 
    21076, 21119, 21166, 21116, 21117, 
    21118, 21087, 21120, 21096, 21113, 
    21097, 21114, 21105, 21108, 21106, 
    21098, 21110, 21111
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 0

Query time 0.00025

JSON explain

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