检查以下代码。

scala> val queries = Map(
                          "df1" -> "select * from tb1",
                          "df2" -> "select * from TB2",
                          "df3" -> "select * from TB3"
                      ) // After reading from config file.

scala> 

queries
.values
.par
.map(spark.sql)
.foreach(_.show(false)) 

// Used .par for parallel loading & all three DataFrame object will be in list & you can do any operation on that, here i am using show function to display values

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+---+

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+---+

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|id |
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+---+