Where in the sqlContext.implicits._ does it define the $\"string\" to represent a dataframe call to the parent dataframe\'s column? Specifically I was confused
sqlContext.implicits._
If you see the following link
class SQLContext.implicits$.StringToColumn Converts $"col name" into an Column.
class SQLContext.implicits$.StringToColumn
Converts $"col name" into an Column.
Here is the link for latest version.