Hi all, I wanted to join the data frame based on spark sql in IntelliJ, and wrote these code lines as below:df1.as('first).join(df2.as('second), $"first._1" === $"second._1")
IntelliJ reported the error for $ and === in red colour. I found $ and === are defined as implicit conversion in org.apache.spark.sql.catalyst.dsl.ExpressionConversions and org.apache.spark.sql.catalyst.dsl.ImplicitOperators, so I was trying to import them to solve the issue, however, it doesn't work.