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From: "David G. Johnston" <david.g.johnston@gmail.com>
Date: Fri, 5 Sep 2025 14:11:32 -0700
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 <CAKFQuwZ5v-+HcoSy3TKOBPk1+TDMcM7iHq-VCh+d-ZvdC3QnMw@mail.gmail.com>
Subject: Re: SELECT List with/without parentheses
To: "jason@starnull.net" <jason@starnull.net>,
	"pgsql-docs@lists.postgresql.org" <pgsql-docs@lists.postgresql.org>
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On Thursday, September 4, 2025, PG Doc comments form <noreply@postgresql.or=
g>
wrote:

> The following documentation comment has been logged on the website:
>
> Page: https://www.postgresql.org/docs/17/sql-select.html
> Description:
>
> Here: https://www.postgresql.org/docs/current/sql-select.html
>
> There is no mention of the difference in PostgreSql behavior if the selec=
t
> list of columns is surrounded by parentheses or not. The difference is
> quite
> dramatic and non-obvious, especially when working with a database driver
> (like pq or pqxx) where the result is packed up in a fairly opaque object=
.
> Just some mention of how using parentheses causes a query to return a "ro=
w"
> object that represents the tuple as a single string vs not using
> parentheses
> where each column is represented individually.
>

That kind of material usually goes in the syntax chapter since it isn=E2=80=
=99t
special to a select command or really any command in particular.

The documentation does explain that to create a row-like composite from
individual columns you use [row](=E2=80=A6).

https://www.postgresql.org/docs/current/sql-expressions.html#SQL-SYNTAX-ROW=
-CONSTRUCTORS

The select command itself states what it does: each column - and the column
list is not parenthesized - becomes a column in the result.

I admit it=E2=80=99s definitely not easy to try making up some new syntax, =
finding
that it works, then looking for the feature in the documentation from the
syntax alone.  But that is also not usually how one learns.  In short, I=E2=
=80=99m
against updating =E2=80=9Cselect=E2=80=9D but would entertain some other co=
ncrete
suggestion since I don=E2=80=99t find this scenario rare enough to just ign=
ore and
deal with via Q&A.

David J.

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On Thursday, September 4, 2025, PG Doc comments form &lt;<a href=3D"mailto:=
noreply@postgresql.org">noreply@postgresql.org</a>&gt; wrote:<br><blockquot=
e class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc sol=
id;padding-left:1ex">The following documentation comment has been logged on=
 the website:<br>
<br>
Page: <a href=3D"https://www.postgresql.org/docs/17/sql-select.html" target=
=3D"_blank">https://www.postgresql.org/<wbr>docs/17/sql-select.html</a><br>
Description:<br>
<br>
Here: <a href=3D"https://www.postgresql.org/docs/current/sql-select.html" t=
arget=3D"_blank">https://www.postgresql.org/<wbr>docs/current/sql-select.ht=
ml</a><br>
<br>
There is no mention of the difference in PostgreSql behavior if the select<=
br>
list of columns is surrounded by parentheses or not. The difference is quit=
e<br>
dramatic and non-obvious, especially when working with a database driver<br=
>
(like pq or pqxx) where the result is packed up in a fairly opaque object.<=
br>
Just some mention of how using parentheses causes a query to return a &quot=
;row&quot;<br>
object that represents the tuple as a single string vs not using parenthese=
s<br>
where each column is represented individually.<br>
</blockquote><div><br></div><div>That kind of material usually goes in the =
syntax chapter since it isn=E2=80=99t special to a select command or really=
 any command in particular.</div><div><br></div><div>The documentation does=
 explain that to create a row-like composite from individual columns you us=
e [row](=E2=80=A6).</div><div><br></div><div><a href=3D"https://www.postgre=
sql.org/docs/current/sql-expressions.html#SQL-SYNTAX-ROW-CONSTRUCTORS">http=
s://www.postgresql.org/docs/current/sql-expressions.html#SQL-SYNTAX-ROW-CON=
STRUCTORS</a><br></div><div><br></div><div>The select command itself states=
 what it does: each column - and the column list is not parenthesized - bec=
omes a column in the result.</div><div><br></div><div>I admit it=E2=80=99s =
definitely not easy to try making up some new syntax, finding that it works=
, then looking for the feature in the documentation from the syntax alone.=
=C2=A0 But that is also not usually how one learns.=C2=A0 In short, I=E2=80=
=99m against updating =E2=80=9Cselect=E2=80=9D but would entertain some oth=
er concrete suggestion since I don=E2=80=99t find this scenario rare enough=
 to just ignore and deal with via Q&amp;A.</div><div><br></div><div>David J=
.</div><div><br></div>

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