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From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Arturo Guadagnin <tuirutuiru@gmail.com>,
        "pgsql-sql@lists.postgresql.org" <pgsql-sql@lists.postgresql.org>
Subject: Re: embedded composite types
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Saturday, February 20, 2021, Arturo Guadagnin <tuirutuiru@gmail.com>
> wrote:
>> I’m just wondering whether this is the expected behaviour or if there is
>> any syntactical magic I’m not aware of ....

> https://www.postgresql.org/docs/current/sql-expressions.html#FIELD-SELECTION

Yeah.  Also note that we only recently got around to fixing plpgsql
assignment to allow nested fields; that is

declare p Point2;
...
p.pt1.x = 42;

works in HEAD but not in any released version.

			regards, tom lane