Join Dataframes dynamically using Spark Scala when JOIN columns differ
从上面的链接中，我能够使join表达式正常工作，但是我得到了重复的列，我试图将这些列放到join部分中，但它不起作用，我也可以使用select语句，但是是否存在删除联接行本身中的列的方法，我不想使用Seq，因为列名可能不同。
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