Re: [HACKERS] SQL/JSON in PostgreSQL

2018-01-06 22:02 GMT+01:00 Oleg Bartunov <obartunov(at)gmail(dot)com>:

> On Sat, Jan 6, 2018 at 8:22 AM, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>
> wrote:
> > Hi
> >
> > I am checking the JSONPath related code
> >
> > Questions, notes:
> >
> > 1. jsonpath operators are not consistent with any other .. json, xml ..
> I am
> > missing ?, @> operátors
>
> I have slides about jsonpath
> http://www.sai.msu.su/~megera/postgres/talks/sqljson-pgconf.eu-2017.pdf
>
> > 2. documentation issue - there is "'{"a":[1,2,3,4,5]}'::json *? '$.a[*]
> ? (@
> >> 2)'" - operator *? doesn't exists
>
> There are should be @? operator
>
> > 3. operator @~ looks like too aggressive shortcut - should be better
> > commented
> >
> > What is not clean, if jsonpath should to create some new operators for
> json,
> > jsonb types? It is special filter, defined by type, so from my
> perspective
> > the special operators are not necessary.
>
> It's impossible to distinguish jsonpath from text, so introducing new
> operators
> are easier than everytime explicitly specify jsonpath datatype.
>

There are two possible solutions - special operator or explicit casting. In
this case I am not sure if special operator for this case is good solution.
Probably nobody will use it - because there SQL/JSON functions, but I don't
think so this inconsistency is correct.

I have not strong opinion about it - it will be hidden feature for almost
all users.

> >
> > Regards
> >
> > Pavel
> >
> >
>