On Fri, Oct 23, 2020 at 2:21 PM David G. Johnston
<david.g.johnston@gmail.com> wrote:
> I'm torn here because this would be the first usage of this concept in
> PostgreSQL (I think).
Yeah, I also have some qualms about this design in the context of Postgres.
Particularly because Postgres allows arrays to begin at negative indices.
> Tangentially, I noticed that we have a "starts_with" function but no
> corresponding "end_with".
Ah, interesting. On the other hand, there are both "left" and "right",
"lpad" and "rpad", and "ltrim" and "rtrim". And at least ends_with has the
fairly elegant alternative of "s LIKE '%suffix'".
> It's been a while but there used to be a systemic inertia working against
> adding minor useful functions such as these.
>
> With the new documentation layout I would at least consider updating the
> description for the normal functions with an example on how to formulate
> an expression that works contra-normally, and in the case where there does
> exist such a specialized function, naming it.
Supposing you go this route, which of the options would you envision
mentioning as the converse of split_part?