Subject: Re: range_agg
To: David Fetter <david@fetter.org>
Cc: Jeff Davis <pgsql@j-davis.com>,
 Pgsql Hackers <pgsql-hackers@postgresql.org>
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From: Paul Jungwirth <pj@illuminatedcomputing.com>
Message-ID: <dfaeb39a-4be3-4d9d-fa4c-687fd5446071@illuminatedcomputing.com>
Date: Wed, 10 Jul 2019 07:55:11 -0700
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On 7/9/19 11:24 PM, David Fetter wrote:
>>> I seem to recall that the usual convention (at least in math) is
>>> to use intervals that are generally represented as open on the
>>> infinity side, but that might not fit how we do things.
>>
>> I think it does, unless I'm misunderstanding?
> 
> Oh, I was just wondering about the square bracket on the left side of
> [null, 1).  It's not super important.

Ah, I understand now. Just a typo on my part. Thanks for catching it, 
and sorry for the confusion!

>>> !mr , perhaps?
>>
>> I like that suggestion. Honestly I'm not sure we even want an inverse,
>> but it's so important theoretically we should at least consider
>> whether it is appropriate here. Or maybe "inverse" is the wrong word
>> for this, or there is a different meaning it should have.
> 
> Jeff's suggestion of ~ for complement is better.

Okay, thanks. I like it better too.

Yours,

-- 
Paul              ~{:-)
pj@illuminatedcomputing.com