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Apache Hive: How to convert string to timestamp?

I'm trying to convert the string in REC_TIME column to a timestamp format in hive.

Ex: Sun Jul 31 09:28:20 UTC 2016 => 2016-07-31 09:28:20 

SELECT xxx, UNIX_TIMESTAMP(REC_TIME, "E M dd HH:mm:ss z yyyy") FROM wlogs LIMIT 10;

When I execute the above SQL it returns a NULL value.

Solution

  • Try this :

    select from_unixtime(unix_timestamp("Sun Jul 31 09:28:20 UTC 2016","EEE MMM dd HH:mm:ss zzz yyyy"));

    This works fine if your hive cluster has UTC timezone. Say suppose your server is in CST then you need to do as below to get to UTC;

    select to_utc_timestamp(from_unixtime(unix_timestamp("Sun Jul 31 09:28:20 UTC 2016","EEE MMM dd HH:mm:ss zzz yyyy")),'CST');

    Hope this helps.

    EDIT Hive date functions use the JAVA simple date formater for the patterns . Refer this for the patterns.