Re: BUG #8293: There are no methods to convert json scalar text to text in v9.3 beta2

On Wed, Jul 10, 2013 at 07:07:54PM +0000, jaroslav.potapov@gmail.com wrote:
> The following bug has been logged on the website:
>
> Bug reference:      8293
> Logged by:          Yaroslav Potapov
> Email address:      jaroslav.potapov@gmail.com
> PostgreSQL version: Unsupported/Unknown
> Operating system:   All
> Description:
>
> SELECT '"a\"b"'::json::text
>
>
> returns text: '"a\"b"' ,
> but it must return 'a"b' in my opinion.

I see you didn't get a reply, so let me try.  I am no JSON expert, but I
think what is happening is that the system stores "a\"b" because that is
what a JSON/Javascript interpreter would need to understand that value.
It would convert "a\"b" to a"b.  If we just stored a"b, the interpreter
would throw an error on input.

You can see this a little bit using 9.3 beta to pull values based on
keys:

    SELECT json_extract_path('{"\"a": "b\"c"}'::json, '"a');
     json_extract_path
    -------------------
     "b\"c"
    (1 row)

    SELECT json_extract_path('{"\"a": "b\"c"}'::json, '\"a');
     json_extract_path
    -------------------

    (1 row)

Notice the key is "a, not \"a.

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  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
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