Re: Analysis Function - Mailing list pgsql-performance

From Tom Lane
Subject Re: Analysis Function
Date
Msg-id 14336.1276444704@sss.pgh.pa.us
Whole thread Raw
In response to Re: Analysis Function  (Magnus Hagander <magnus@hagander.net>)
Responses Re: Analysis Function  (Magnus Hagander <magnus@hagander.net>)
List pgsql-performance
Magnus Hagander <magnus@hagander.net> writes:
> On Sun, Jun 13, 2010 at 17:42, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> ... (We presumably want
>> timezone to default to the system timezone setting, but I wonder how
>> we should make that work --- should an empty string be treated as
>> meaning that?)

> Umm. NULL could be made to mean that, or we could provicde two
> different versions - one that takes TZ and one that doesn't.

Using NULL like that seems a bit awkward: for one thing it'd mean the
function couldn't be STRICT, and also it'd be bizarre that only this
one argument could be null without leading to a null result.

And two separate functions isn't good either.  Basically, I think it's
important that there be a way to specify an explicit parameter value
that behaves identically to the default.

> And a third, construct_time(), no?

Yeah, maybe ... do you think there's any demand for it?

            regards, tom lane

pgsql-performance by date:

Previous
From: Magnus Hagander
Date:
Subject: Re: Analysis Function
Next
From: David Jarvis
Date:
Subject: Re: Analysis Function