SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    276627, 276628, 276629, 276630, 276631, 
    276632, 276633, 276634, 276635, 276636, 
    276637, 276638, 276639, 276640, 276641, 
    276642, 276643, 276644, 276645, 276646
  )

Query time 0.00028

JSON explain

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