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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 (
    18, 16, 4, 5, 23, 24, 1, 22, 25, 6, 8, 14, 
    9, 10, 19, 21
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 0

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_product_review_prepared_data",
      "access_type": "ALL",
      "possible_keys": ["PRIMARY"],
      "rows": 52,
      "filtered": 30.76922989,
      "attached_condition": "cscart_product_review_prepared_data.storefront_id = 0 and cscart_product_review_prepared_data.product_id in (18,16,4,5,23,24,1,22,25,6,8,14,9,10,19,21)"
    }
  }
}

Result

product_id	average_rating	reviews_count
5	3.67	3
1	4.00	3
23	3.00	1
8	4.00	1