I need to get the minimum value from the Spark data frame and transform it. Currently, I just get this value and transform it using DateTime, however, I need it in the unix_timestamp format as the result. So how can I convert DateTime to unix_timestamp either using Scala functions or Spark functions?
Here is my current code which for now returns DateTime:
val minHour = new DateTime(df.agg(min($"event_ts"))
.as[Timestamp].collect().head))
.minusDays(5)
.withTimeAtStartOfDay())
I tried using Spark functions as well but I was not able to switch timestamp to start time of day (which can be achieved using DateTime withTimeAtStartOfDay function):
val minHour = new DateTime(df.agg(min($"event_ts").alias("min_ts"))
.select(unix_timestamp(date_sub($"min_ts", 5)))
.as[Long].collect().head)