The JoinRowSetImpl class had a bug in it at the time of this article?s writing that rendered the ability to specify multiple columns for the MatchColumn as useless.

在本文编写之际，JoinRowSetImpl类有一个bug，它允许指定多个列作为无用的MatchColumn。

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It \ s time for class.

上课时间到了。

youdao

It "s time for class."

上课时间到了。

youdao

It "s time for class."

上课时间到了。

youdao