Re: Why extract( ... from timestamp ) is not immutable?

On Wed, Jan 25, 2012 at 08:54:44AM -0800, Adrian Klaver wrote:
> > Personally, I think that extract(epoch from timestamp) should assume
> > that the timestamp is UTC.
>
> What if it isn't?

then you can always correct it with "at time zone 'some specific time
zone'"

but you can't correct it the other way.

> > Or that there should be a way to do it - by "it" i mean - extract epoch
> > value from timestamp value in immutable way.
>
> Have a timezone value on the timestamp. If the data you are working with is
> stored as timestamp with time zone then the timestamps represent a point in
> time.

I do have. But you can't have index on epoch from timestamptz.
and while you can have iundex on epoch from timestamp, it is not
correct.

depesz

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