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From Brad Cavanagh <brad.cavan...@gmail.com>
Subject Re: Timestamp, Epoch Time, Functions and other Frustrations
Date Fri, 04 Jan 2013 16:25:34 GMT
Try multiplying your values by 1000, then running the conversions. I bet they expect milliseconds
since the epoch instead of seconds.

Brad. 

On 2013-01-04, at 8:03 AM, John Omernik <john@omernik.com> wrote:

> Greetings all. I am getting frustrated with the documentation and lack of intuitiveness
in Hive relating to timestamps and was hoping I could post here and get some clarification
or other ideas. 
> 
> I have a field that is a string, but is actually a 10 digit int representation of epoch
time, I am going to list out the results of various functions.
> 
> Value = 1356588013
> 
> Hive:
> 
> from_unixtime(Value) = 2012-12-27 00:00:13 (Timezone CST on the system time, so that
works)
> cast(value as timestamp) = 1970-01-16 10:49:48.013
> cast(cast(value as int) as timestamp = 1970-01-16 10:49:48.013
> from_utc_timestamp(starttime, 'GMT') = 1970-01-16 10:49:48.013
> from_utc_timestamp(starttime, 'CST') = 1970-01-16 04:49:48.013
> 
> 
> Epoch Converter - http://www.epochconverter.com/
> 
> Thu, 27 Dec 2012 06:00:13 GMT - GMT Representation of the time
> Thu Dec 27 2012 00:00:13 GMT-6 - My Timezone representation
> 
> Ok Given all of these representations... how do I get the Value ( a valid epoch time)
into a GMT time basically, 2012-12-27 06:00:13 without just doing math. (Math is error prone
on system as we move across timezone). Why doesn't the casting of the value to timestamp or
even the casting of the int cast of the time stamp work?   Why does it read 1970?  This is
very frustrating and should be more intuitive.  Please advise. 
> 
> 

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