Re: JSON doc example (matchiness) - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: JSON doc example (matchiness)
Date
Msg-id YJXt3noQYth06bqM@paquier.xyz
Whole thread Raw
In response to JSON doc example (matchiness)  (Erik Rijkers <er@xs4all.nl>)
Responses Re: JSON doc example (matchiness)
List pgsql-hackers
On Fri, May 07, 2021 at 10:18:44PM +0200, Erik Rijkers wrote:
>
> The JSON doc has this example (to show the need for double backslash):
>
> $ ? (@ like_regex "^\\d+$")
>
>
> The example is not wrong exactly, and can be cast to jsonpath, but as-is can
> never match anything.
>
> I think it'd be helpful to provide that example so that it more probably
> matches when the user does a quick trial.
>
> Llet's change it to something like:
>
> $.* ? (@ like_regex "^\\d+$")

Ah, I see.  What you are telling here is that we match the regex on
the full JSON string, which is pretty useless, and you are suggesting
to change things so as we'd match with the key names at the first
level.  Makes sense.

This paragraph of the docs say:
"For example, to match strings that contain only digits"
Could we be more precise here?  "strings" looks to much generic to
me in this context when actually referring to a set of path of keys in
a JSON blob.
--
Michael

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