Re: Named Operators

On Thu, Jan 12, 2023 at 1:49 AM Matthias van de Meent
<boekewurm+postgres(at)gmail(dot)com> wrote:
>
> On Thu, 12 Jan 2023 at 10:16, Gurjeet Singh <gurjeet(at)singh(dot)im> wrote:
> >
> > Technically correct name of this feature would be Readable Names for
> > Operators, or Pronounceable Names for Operators. But I'd like to call
> > it Named Operators.
> >
> > With this patch in place, the users can name the operators as
> > :some_pronounceable_name: instead of having to choose from the special
> > characters like #^&@.
> > [...]
> > I think Named Operators will significantly improve the readability
> > of queries.
>
> Couldn't the user better opt to call the functions that implement the
> operator directly if they want more legible operations? So, from your
> example, `SELECT box_add(a, b)` instead of `SELECT a :add_point: b`?

Matter of taste, I guess. But more importantly, defining an operator
gives you many additional features that the planner can use to
optimize your query differently, which it can't do with functions. See
the COMMUTATOR, HASHES, etc. clause in the CREATE OPERATOR command.

https://www.postgresql.org/docs/current/sql-createoperator.html

This proposal is primarily a replacement for the myriad of
hard-to-pronounce operators that users have to memorize. For example,
it'd be nice to have readable names for the PostGIS operators.

https://postgis.net/docs/reference.html#Operators

For someone who's reading/troubleshooting a PostGIS query, when they
encounter operator <<| — in the query for the first time, they'd have
to open up the docs. But if the query used the :strictly_below:
operator, there's no need to switch to docs and lose context.

> I'm -1 on the chosen syntax; :name: shadows common variable
> substitution patterns including those of psql.

Ah, thanks for reminding! Early on when I hadn't written code yet, I
remember discarding colon : as a delimiter choice, precisely because
it is used for using variables in psql, and perhaps in some drivers,
as well. But in the rush of implementing and wrangling code, I forgot
about that argument altogether.

I'll consider using one of the other special characters. Do you have
any suggestions?

Best regards,
Gurjeet
http://Gurje.et