Oh, that's a good point. Do you think a hyperlink like the following might be an improvement?
channel
Name of the notification channel to be signaled (any <a
href="https://www.postgresql.org/docs/11/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS">identifier</a>)
If there had been a hyperlink I believe I might have clicked it and found this out sooner.
On Tue, Dec 18, 2018, at 6:57 PM, David G. Johnston wrote:
> On Tue, Dec 18, 2018 at 5:36 PM PG Bug reporting form
> <noreply@postgresql.org> wrote:
> >
> > The following bug has been logged on the website:
> >
> > Bug reference: 15558
> > Logged by: Andy Edwards
> > Email address: jedwards@fastmail.com
> > PostgreSQL version: 11.1
> > Operating system: (irrelevant)
> > Description:
> >
> > After debugging why notifications weren't getting delivered, I discovered
> > the following:
> >
> > # LISTEN "pg/tables/TagNotificationTriggers/tag/_org/1/JSON
> > Test/battery/1/lifetimeWh";
> > NOTICE: identifier "pg/tables/TagNotificationTriggers/tag/_org/1/JSON
> > Test/battery/1/lifetimeWh" will be truncated to
> > "pg/tables/TagNotificationTriggers/tag/_org/1/JSON Test/battery/"
> >
> > I haven't seen a mention of this channel length limit in any version of the
> > documentation for NOTIFY. I wish it were in the documentation, because then
> > I would have found out about this limit before deciding to use Postgres
> > notifications, and chosen to use Redis notifications from the beginning.
>
> Since it is just another name/identifier it is the same limit and
> behavior as is present for table names, column names, type names,
> etc...
>
> The length of identifiers is covered in the general section covering syntax:
>
> https://www.postgresql.org/docs/11/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS
>
> Default length for identifiers is identified as being 63 bytes -
> though technically (but not usefully) is system dependent at compile
> time.
>
> It is intentional to not spam the documentation with such a
> wide-ranging dynamic everywhere it might come into play...I'm
> undecided whether NOTIFY is deserving of an exception...
>
> David J.