Re: PG 12 draft release notes

On Mon, May 13, 2019 at 6:52 AM Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>
> On Sun, May 12, 2019 at 09:49:40AM -0400, Bruce Momjian wrote:
> > On Sun, May 12, 2019 at 10:00:38AM +0300, Oleg Bartunov wrote:
> > > Bruce,
> > >
> > > I noticed that jsonpath in your version is mentioned only in functions
> > > chapter, but commit
> > > 72b6460336e86ad5cafd3426af6013c7d8457367 is about implementation of
> > > SQL-2016 standard. We implemented JSON Path language as a jsonpath
> > > datatype with a bunch of support functions, our implementation
> > > supports 14 out of 15 features and it's the most complete
> > > implementation (we compared oracle, mysql and ms sql).
> >
> > Glad you asked. I was very confused about why a data type was added for
> > a new path syntax. Is it a new storage format for JSON, or something
> > else? I need help on this.
>
> I talked to Alexander Korotkov on chat about this. The data types are
> used as arguments to the functions, similar to how tsquery and tsvector
> are used for full text search.
>
> Therefore, the data types are not really useful on their own, but as
> support for path functions. However, path functions are more like JSON
> queries, rather than traditional functions, so it odd to list them under
> functions, but there isn't a more reasonable place to put them.
>
> Alexander researched how we listed full text search in the release notes
> that added the feature, but we had "General" category at that time that
> we don't have now.

I attached slide about our Jsonpath implementation in Postgres, it
summarizes the reasons to have jsonpath data type. But my point was:
JSON Path is a part of SQL-2016 standard and I think it's worth to
mention it, not just a set of jsonb functions.

>
> --
> Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
> EnterpriseDB http://enterprisedb.com
>
> + As you are, so once was I. As I am, so you will be. +
> + Ancient Roman grave inscription +

--
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company