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Sean Owen commented on SPARK-17971: ----------------------------------- Oops I copied the wrong link. I mean : https://spark.apache.org/docs/1.6.2/api/java/org/apache/spark/sql/functions.html#from_utc_timestamp(org.apache.spark.sql.Column,%20java.lang.String) A UNIX timestamp defines the same point in time and does not depend on a timezone to interpret it. I think we are clear on that and it isn't the point. You just need the methods that don't use system tz. > Unix timestamp handling in Spark SQL not allowing calculations on UTC times > --------------------------------------------------------------------------- > > Key: SPARK-17971 > URL: https://issues.apache.org/jira/browse/SPARK-17971 > Project: Spark > Issue Type: Bug > Components: Spark Core, SQL > Affects Versions: 1.6.2 > Environment: MacOS X JDK 7 > Reporter: Gabriele Del Prete > > In our Spark data pipeline we store timed events using a bigint column called > 'timestamp', the values contained being Unix timestamp time points. > Our datacenter servers Java VMs are all set up to start with timezone set to > UTC, while developer's computers are all in the US Eastern timezone. > Given how Spark SQL datetime functions work, it's impossible to do > calculations (eg. extract and compare hours, year-month-date triplets) using > UTC values: > - from_unixtime takes a bigint unix timestamp and forces it to the computer's > local timezone; > - casting the bigint column to timestamp does the same (it converts it to the > local timezone) > - from_utc_timestamp works in the same way, the only difference being that it > gets a string as input instead of a bigint. > The result of all of this is that it's impossible to extract individual > fields of a UTC timestamp, since all timestamp always get converted to the > local timezone. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org