SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    276455, 276456, 276457, 276458, 276459, 
    276460, 276461, 276462, 276463, 276464, 
    276465, 276466, 276467, 276468, 276469, 
    276470, 276471, 276472, 276473, 276474
  )

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}