Re: row_to_json(), NULL values, and AS - Mailing list pgsql-bugs

From Robert Haas
Subject Re: row_to_json(), NULL values, and AS
Date
Msg-id CA+TgmoYnWZVnDJofLZ1x+rPN=R=362tUfUacnyMymqk0R3Mx=g@mail.gmail.com
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In response to Re: row_to_json(), NULL values, and AS  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: row_to_json(), NULL values, and AS  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
On Fri, Jun 15, 2018 at 10:53 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> I'm a bit hesitant to muck with this behavior, given that it's stood
> for ~20 years.  However, if we did want to touch it, maybe the right
> thing would be to give up the absolutist position that f(x) and x.f
> are exactly interchangeable.  We could say instead that we prefer the
> function interpretation if function syntax is used, and the column
> interpretation if column syntax is used.  I don't know how likely
> that is to break existing apps ... perhaps not very, but I wouldn't
> risk back-patching it in any case.

For the record, I fear that this change (committed as
b97a3465d73bfc2a9f5bcf5def1983dbaa0a26f8) is going to break more
things than have been foreseen in this thread.  I do not have a
specific theory about how that's going to happen, just vague unease.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


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