Thread: strip nulls functions for json and jsonb

As discussed recently, here is an undocumented patch for
json_strip_nulls and jsonb_strip_nulls.

cheers

andrew

On 10/16/2014 04:12 PM, Pavel Stehule wrote:
>
>
> 1. missing documentation
>
> 2. I miss more comments related to this functions. This code is
> relative simple, but some more explanation can be welcome.
>
> 3. why these functions are marked as "stable"?
>
>

New patch:

Docs added, functions marked immutable, more comments added.

cheers

andrew

On 10/26/2014 03:50 PM, Pavel Stehule wrote:
> Hi
>
> I have a question,
>
> what is expected result of null strip of
>
> {"a": {"b": null, "c", null"} }
>
> ?
>


Please remember not to top-post.

The above is not legal json, so the answer would be an error.

cheers

andrew

On 10/26/2014 04:14 PM, Thom Brown wrote:
> On 26 October 2014 20:07, Andrew Dunstan <andrew@dunslane.net 
> <mailto:andrew@dunslane.net>> wrote:
>
>
>     On 10/26/2014 03:50 PM, Pavel Stehule wrote:
>
>         Hi
>
>         I have a question,
>
>         what is expected result of null strip of
>
>         {"a": {"b": null, "c", null"} }
>
>         ?
>
>
>
>     Please remember not to top-post.
>
>     The above is not legal json, so the answer would be an error.
>
>
> I believe Pavel means:
>
> {"a": {"b": null, "c": null} }

This is the expected result:
   andrew=# select json_strip_nulls('{"a": {"b": null, "c": null} }');     json_strip_nulls   ------------------
{"a":{}}  (1 row)
 


It is NOT expected that we replace an empty object with NULL (and then 
strip it if it's a field value of an outer level object).

cheers

andrew

On 10/26/2014 04:22 PM, Pavel Stehule wrote:
>
>
> 2014-10-26 21:18 GMT+01:00 Andrew Dunstan <andrew@dunslane.net
> <mailto:andrew@dunslane.net>>:
>
>
>     On 10/26/2014 04:14 PM, Thom Brown wrote:
>
>         On 26 October 2014 20:07, Andrew Dunstan <andrew@dunslane.net
>         <mailto:andrew@dunslane.net> <mailto:andrew@dunslane.net
>         <mailto:andrew@dunslane.net>>> wrote:
>
>
>             On 10/26/2014 03:50 PM, Pavel Stehule wrote:
>
>                 Hi
>
>                 I have a question,
>
>                 what is expected result of null strip of
>
>                 {"a": {"b": null, "c", null"} }
>
>                 ?
>
>
>
>             Please remember not to top-post.
>
>             The above is not legal json, so the answer would be an error.
>
>
>         I believe Pavel means:
>
>         {"a": {"b": null, "c": null} }
>
>
>     This is the expected result:
>
>        andrew=# select json_strip_nulls('{"a": {"b": null, "c": null} }');
>          json_strip_nulls
>        ------------------
>          {"a":{}}
>        (1 row)
>
>
>     It is NOT expected that we replace an empty object with NULL (and
>     then strip it if it's a field value of an outer level object).
>
>
> ok,
>
> This case should be in regress test probably
>
>

Patch attached.

cheers

andrew