The first item of replication metadata we 'll discuss is the Update Sequence Number(USN) ( USN ). 我们要讨论的第一个复制元数据项目是更新序列号(USN)(USN)。
The Update Sequence Number(USN) on a domain controller is incremented by both types of write operations, which means that it is incremented whenever changes are replicated in from another DC. 两种类型的写入操作都可增加域控制器上的更新序列号(USN),这意味着每当从其他DC复制了更改时,该序列号都会增加。
Since every independently persistable object in a repository already has a monotonically increasing Update Sequence Number(USN), why not use that instead of a custom property for the counter value? 既然储存库中的每个独立的可持久化对象都有一个递增的UpdateSequenceNumber,为什么不使用USN取代计数器值的定制属性?
This can be done by using a timestamp or sequence number contained in the row, or by adding every column in the row to the WHERE clause of the UPDATE. 这可以通过使用数据行中包含的时间戳或序列号来进行,也可将数据行的每个列字段添加到UPDATE的WHERE子句中。