SELECT 
  product_id, 
  amount 
FROM 
  cscart_warehouses_sum_products_amount 
WHERE 
  1 
  AND product_id IN (
    276674, 276675, 276676, 276677, 276678, 
    276679, 276680, 276681, 276682, 276683, 
    276684, 276685, 276686, 276687, 276688, 
    276689, 276690, 276691, 276692, 276693
  )

Query time 0.00034

JSON explain

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