authuir commented on a change in pull request #12420:
URL: https://github.com/apache/flink/pull/12420#discussion_r458831384
##########
File path: docs/dev/table/streaming/joins.zh.md
##########
@@ -300,25 +285,26 @@ FROM
ON r.currency = o.currency
{% endhighlight %}
-Each record from the probe side will be joined with the current version of the
build side table. In our example, the query is using the processing-time
notion, so a newly appended order would always be joined with the most recent
version of `LatestRates` when executing the operation. Note that the result is
not deterministic for processing-time.
+探针侧表中的每个记录都将与构建侧表的当前版本所关联。 在此示例中，查询使用`处理时间`作为处理时间，因而新增订单将始终与表 `LatestRates`
的最新汇率执行 Join 操作。 注意，结果对于处理时间来说不是确定的。
+
+与[常规 Join](#regular-joins) 相比，尽管构建侧表的数据发生了变化，但时态表 Join 的变化前结果不会随之变化。而且时态表 Join
运算非常轻量级且不会保留任何状态。
-In contrast to [regular joins](#regular-joins), the previous results of the
temporal table join will not be affected despite the changes on the build side.
Also, the temporal table join operator is very lightweight and does not keep
any state.
+与[时间区间 Join](#interval-joins) 相比，时态表 Join 没有定义决定哪些记录将被 Join 的时间窗口。
+探针侧的记录将总是与构建侧在对应`处理时间`的最新数据执行 Join。因而构建侧的数据可能是任意旧的。
-Compared to [interval joins](#interval-joins), temporal table joins do not
define a time window within which the records will be joined.
-Records from the probe side are always joined with the build side's latest
version at processing time. Thus, records on the build side might be
arbitrarily old.
+[时态表函数 Join](#join-with-a-temporal-table-function) 和时态表 Join 都有类似的功能，但是有不同的
SQL 语法和 runtime 实现：
-Both [temporal table function join](#join-with-a-temporal-table-function) and
temporal table join come from the same motivation but have different SQL syntax
and runtime implementations:
-* The SQL syntax of the temporal table function join is a join UDTF, while the
temporal table join uses the standard temporal table syntax introduced in
SQL:2011.
-* The implementation of temporal table function joins actually joins two
streams and keeps them in state, while temporal table joins just receive the
only input stream and look up the external database according to the key in the
record.
-* The temporal table function join is usually used to join a changelog stream,
while the temporal table join is usually used to join an external table (i.e.
dimension table).
+* 时态表函数 Join 的 SQL 语法是一种 Join 用户定义生成表函数(UDTF，User-Defined Table-Generating
Functions)，而时态表 Join 使用了 SQL:2011 标准引入的标准时态表语法。
+* 时态表函数 Join 的实现实际上是 Join 两个流并保存在 state 中，而时态表 Join 只接受唯一的输入流，并根据记录的键值查找外部数据库。
+* 时态表函数 Join 通常用于与变更日志流执行 Join，而时态表 Join 通常与外部表（例如维度表）执行 Join 操作。
-Such behaviour makes a temporal table join a good candidate to express stream
enrichment in relational terms.
+这种做法让时态表 Join 成为一个很好的用于表达不同流之间关联的方法。
-In the future, the temporal table join will support the features of temporal
table function joins, i.e. support to temporal join a changelog stream.
+将来，时态表 Join 将支持时态表函数 Join 的功能，即支持时态 Join 变更日志流。
-### Usage
+### 用法
Review comment:
Done
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
