Thread: timetz storage vs timestamptz

timetz storage vs timestamptz

From
"Jim C. Nasby"
Date:
Why is it timestamptz can store a date and time to 1 microsecond in 8
bytes but a timetz needs 12 to store just the time to 1 microsecond?
-- 
Jim Nasby                                            jim@nasby.net
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)


Re: timetz storage vs timestamptz

From
Tom Lane
Date:
"Jim C. Nasby" <jim@nasby.net> writes:
> Why is it timestamptz can store a date and time to 1 microsecond in 8
> bytes but a timetz needs 12 to store just the time to 1 microsecond?

It's tracking the timezone explicitly ... something that timestamptz
really ought to do too.
        regards, tom lane


Re: timetz storage vs timestamptz

From
Jim Nasby
Date:
On Oct 3, 2006, at 5:32 PM, Tom Lane wrote:
> "Jim C. Nasby" <jim@nasby.net> writes:
>> Why is it timestamptz can store a date and time to 1 microsecond in 8
>> bytes but a timetz needs 12 to store just the time to 1 microsecond?
>
> It's tracking the timezone explicitly ... something that timestamptz
> really ought to do too.

Wow, the docs are totally unclear on that. I believe that explains  
bug 2661.

Yes, it would be nice to store the timezone in timestamptz or an  
equivalent, but there's also a use for the current behavior. In many  
cases, you don't care what the original timezone was; you just want  
to make sure that everything is getting stored in UTC (and then  
converted to your local timezone on the way back out).

I'm thinking time[stamp], time[stamp]tz (which should do what timetz  
does), and time[stamp]utc (doing what timestamptz does).

In the meantime I'll try and clarify the docs on this.
--
Jim Nasby                                    jimn@enterprisedb.com
EnterpriseDB      http://enterprisedb.com      512.569.9461 (cell)