AWS Dynamodb使用算术表达式更新表达式

Question

假设我的数据库中有此数据。

Fetch READ_UNCOMMITTED at offset 1000 for partition test-0 returned fetch data (error=NONE, highWaterMark=1000, lastStableOffset = -1, logStartOffset = 0, abortedTransactions = null, recordsSizeInBytes=10486) Added READ_UNCOMMITTED fetch request for partition test-0 at offset 1000 to node localhost:9092 (id: 0 rack: null) Sending READ_UNCOMMITTED fetch for partitions [test-0] to broker localhost:9092 (id: 0 rack: null)

现在，我需要更新商品。我的要求是

Delete * From Table1 Insert Into Table1

详细的更新参数=

{ stdardCount :15, currentCount:10 }

我遇到以下错误

‘无效的UpdateExpression：语法错误；令牌：“-”，附近：“ stdardCount-：modifiedCount””

截至目前，我正在从数据库中获取数据，然后减去