下面的DynamoDB表有一个等于date的分区键，所以我可以很容易地每天查询。我知 prop 有相同分区键的项存储在相同的分区中，并按其排序键排序。
但是，本例中的排序键是错误的，因为TransferId不像是我可以排序的日期。
应使用哪个排序键才能查询特定日期的最后一项？“Exchange：Time”？

+----------+------------------------------------------+---------+--------------------------------------------+------------+----------+------------+---------+-----------+---------------------------+----------------+--------------------------------------------------------------------+----------------------------------+--------------+------------------------------+
|    PK    |                    SK                    | Account |                  Address                   | AddressTag | Exchange | Instrument | Network | Quantity  |           Time            | TransactionFee |                           TransactionId                            |            TransferId            | TransferType |          UpdatedAt           |
+----------+------------------------------------------+---------+--------------------------------------------+------------+----------+------------+---------+-----------+---------------------------+----------------+--------------------------------------------------------------------+----------------------------------+--------------+------------------------------+
| 20221217 | Binance:1b56485f6a3446c3b883f4f485039260 | main    | 0xF76d3f20bF155681b0b983bFC3ea5fe43A2A6E3c | null       | Binance  | USDT       | ETH     | 97.500139 | 2022-12-17T14:59:12+00:00 |            3.2 | 0x46d28f7d0e1e5b1d074a65dcfbb9d90b3bcdc7e6fca6b1f1f7abb5ab219feb24 | 1b56485f6a3446c3b883f4f485039260 |            0 | 2023-01-27T18:00:00.5930186Z |
| 20221217 | Binance:4747f6ecc74f4dd8a4b565e0f15bcf79 | main    | 0xF76d3f20bF155681b0b983bFC3ea5fe43A2A6E3c | null       | Binance  | USDT       | ETH     | 3107.4889 | 2022-12-17T15:38:23+00:00 |            3.2 | 0xbb2b92030b988a0184ba02e2e754b7a7f0f963c496c4e3473509c6fe6b54a41d | 4747f6ecc74f4dd8a4b565e0f15bcf79 |            0 | 2023-01-27T18:00:00.2944534Z |
+----------+------------------------------------------+---------+--------------------------------------------+------------+----------+------------+---------+-----------+---------------------------+----------------+--------------------------------------------------------------------+----------------------------------+--------------+------------------------------+

我想代码应该如下所示：

var date = DateTimeOffset.UtcNow.ToString("yyyyMMdd");

var request = new QueryRequest
{
    TableName = "transfers-dev",
    KeyConditionExpression = "#date = :date",
    ExpressionAttributeNames = new Dictionary<string, string> { { "#date", "PK" } },
    ExpressionAttributeValues = new Dictionary<string, AttributeValue> { { ":date", new AttributeValue { S = date } } },
    ScanIndexForward = false,
    Limit = 1
};
var response = await client.QueryAsync(request);

return response.Items.First();