Message-ID: <4f0d336f-3de6-4671-b7d2-b7d8e3cbf790@dunslane.net>
Date: Fri, 17 Apr 2026 08:40:41 -0400
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Subject: Re: Reject invalid databases in pg_get_database_ddl()
To: Amit Langote <amitlangote09@gmail.com>, Lakshmi N <lakshmin.jhs@gmail.com>
Cc: Hu Xunqi <huxunqi.08@gmail.com>, Euler Taveira <euler@eulerto.com>,
 "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
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From: Andrew Dunstan <andrew@dunslane.net>
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On 2026-04-17 Fr 12:22 AM, Amit Langote wrote:
> On Fri, Apr 17, 2026 at 1:21 PM Lakshmi N <lakshmin.jhs@gmail.com> wrote:
>> On Thu, Apr 16, 2026 at 8:31 PM Amit Langote <amitlangote09@gmail.com> wrote:
>>> On Fri, Apr 17, 2026 at 11:49 AM Hu Xunqi <huxunqi.08@gmail.com> wrote:
>>>> On Fri, Apr 17, 2026 at 10:16 AM Amit Langote <amitlangote09@gmail.com> wrote:
>>>> +       /*
>>>> +        * Reject invalid databases: datconnlimit = -2 would be emitted as
>>>> +        * CONNECTION LIMIT = -2, which cannot be executed.
>>>> +        */
>>>>
>>>> This comment looks a bit too centered on datconnlimit=-2, but the real issue is that an invalid pg_database row should not be deparsed into DDL. So, maybe rephrase like:
>>>>
>>>> /*
>>>> * Reject invalid databases. Deparsing a pg_database row in invalid state
>>>> * can produce SQL that is not executable, such as CONNECTION LIMIT = -2.
>>>> */
>>> I was trying to be precise about datconnlimit = -2 being the thing
>>> that produces invalid SQL. But your version covers that with the "such
>>> as CONNECTION LIMIT = -2" example, and it's closer to the original,
>>> which was on the right track, just needed to be more precise. Let's go
>>> with it.
>> This looks good to me. Thank you for reviewing and making the changes!
> Pushed.
>

Thanks for jumping on this.


cheers


andrew

--
Andrew Dunstan
EDB: https://www.enterprisedb.com