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

Hi

2014-10-04 1:23 GMT+02:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

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

It is looking well

Regards

Pavel

>
> cheers
>
> andrew
>
>
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>
>

Hello

I checked this patch.

1. There is a consensus we want this feature.

2. This patch implement just this mentioned feature. There is no objection
against design.

3. It is possible to apply this patch and compile without warnings.

4. I tested null stripping on large json, jsonb values without problems.

5. regress tests are enough

6. code is well formatted

Objections & questions:

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"?

Regards

Pavel

2014-10-04 1:23 GMT+02:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

> As discussed recently, here is an undocumented patch for json_strip_nulls
> and jsonb_strip_nulls.
>
> cheers
>
> andrew
>
>
> --
> Sent via pgsql-hackers mailing list (pgsql-hackers(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-hackers
>
>

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

Hi

I have a question,

what is expected result of null strip of

{"a": {"b": null, "c", null"} }

?

2014-10-26 19:59 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

>
> 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 26 October 2014 20:07, Andrew Dunstan <andrew(at)dunslane(dot)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} }

--
Thom

On 10/26/2014 04:14 PM, Thom Brown wrote:
> On 26 October 2014 20:07, Andrew Dunstan <andrew(at)dunslane(dot)net
> <mailto:andrew(at)dunslane(dot)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

2014-10-26 21:18 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

>
> On 10/26/2014 04:14 PM, Thom Brown wrote:
>
>> On 26 October 2014 20:07, Andrew Dunstan <andrew(at)dunslane(dot)net <mailto:
>> andrew(at)dunslane(dot)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

Thank you

Pavel

>
> cheers
>
> andrew
>
>

On 10/26/2014 04:22 PM, Pavel Stehule wrote:
>
>
> 2014-10-26 21:18 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net
> <mailto:andrew(at)dunslane(dot)net>>:
>
>
> On 10/26/2014 04:14 PM, Thom Brown wrote:
>
> On 26 October 2014 20:07, Andrew Dunstan <andrew(at)dunslane(dot)net
> <mailto:andrew(at)dunslane(dot)net> <mailto:andrew(at)dunslane(dot)net
> <mailto:andrew(at)dunslane(dot)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

Hi

I am sending a final review of this patch:

0. this patch implements null fields stripping. It does exactly what was
proposed and we would to have this feature in core. It is requested feature
for JSON types.

1. there is no problem with patch apply and with compilation - one warning
is fixed in attachments

2. code is relative small and clean, I have no any objection

3. there is necessary regress tests and related documentation.

I have no any objection - this patch is ready for commiter.

Thank you for patch

Regards

Pavel

2014-10-26 21:57 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net>:

>
> On 10/26/2014 04:22 PM, Pavel Stehule wrote:
>
>>
>>
>> 2014-10-26 21:18 GMT+01:00 Andrew Dunstan <andrew(at)dunslane(dot)net <mailto:
>> andrew(at)dunslane(dot)net>>:
>>
>>
>> On 10/26/2014 04:14 PM, Thom Brown wrote:
>>
>> On 26 October 2014 20:07, Andrew Dunstan <andrew(at)dunslane(dot)net
>> <mailto:andrew(at)dunslane(dot)net> <mailto:andrew(at)dunslane(dot)net
>> <mailto:andrew(at)dunslane(dot)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
>