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From: jian he <jian.universality@gmail.com>
Date: Sun, 29 Dec 2024 10:48:51 +0800
Message-ID: 
 <CACJufxEk16ArmFuTV9VYi6DJaZ+9Jrbt0-u0Zuov7sk-vpg_Dg@mail.gmail.com>
Subject: Re: Re: proposal: schema variables
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Dmitry Dolgov <9erthalion6@gmail.com>,
 Laurenz Albe <laurenz.albe@cybertec.at>,
	Erik Rijkers <er@xs4all.nl>, Michael Paquier <michael@paquier.xyz>,
	Amit Kapila <amit.kapila16@gmail.com>, DUVAL REMI <REMI.DUVAL@cheops.fr>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Sun, Dec 29, 2024 at 5:50=E2=80=AFAM Pavel Stehule <pavel.stehule@gmail.=
com> wrote:
>
> Hi
>
>
>> ------------------<<>>>---------------
>> + else
>> + {
>> + /* the last field of list can be star too */
>> + Assert(IsA(field2, A_Star));
>> +
>> + /*
>> + * In this case, the field1 should be variable name. But
>> + * direct unboxing of composite session variables is not
>> + * supported now, and then we don't need to try lookup
>> + * related variable.
>> + *
>> + * Unboxing is supported by syntax (var).*
>> + */
>> + return InvalidOid;
>> + }
>> I don't fully understand the above comments,
>
>
> The parser allows only two syntaxes - identifier.identifier or identifier=
.star. Second
> syntax is not supported by session variables, and then I didn't try to se=
arch for the variable.
> Some users can be confused by similar syntaxes identifier.* and (identifi=
er).* Only
> second syntax is composite unboxing, and only second syntax is supported =
for
> session variables.
>
> Maybe the note about unboxing is messy there?
>
>> add
>> `elog(INFO, "%s:%d called", __FILE__, __LINE__); ` within the ELSE branc=
h.
>> Then I found out the ELSE branch doesn't have coverage tests.
>
>
> I don't understand this comment? I don't use elog(INFO anywhere
>
>

sorry for confusion, i mean,
i added " elog(INFO", the regress test is still successful,
therefore it means the above ELSE branch code doesn't have coverage tests.