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* remove null values from json
@ 2016-01-15 20:24 Michael Moore <michaeljmoore@gmail.com>
0 siblings, 1 reply; 2+ messages in thread
From: Michael Moore @ 2016-01-15 20:24 UTC (permalink / raw)
To: pgsql-sql
This is ALMOST what I want:
select json_strip_nulls ('[{ "f1":1 , "f2":null , "f3":"NULL" , "f4":""
}]');
the result is:
"[{"f1":1,"f3":"NULL","f4":""}]"
As you can see, the "f2" object has been removed. I would *also* like to
remove the f3 and f4 objects.
I realize I won't be able to use the json_strip_nulls function to do this.
I could brute force it by doing "json to array" then looping through the
array and picking only the objects I want, and then using the chosen
objects to build an new JSON document.
I suspect there is a more elegant way to accomplish the same objective.
Ideas?
PS. It would be great to have a json_strip_values (json, array) where array
contains the list of values you want removed.
^ permalink raw reply [nested|flat] 2+ messages in thread
* Re: remove null values from json
@ 2016-01-19 18:09 Pavel Stehule <pavel.stehule@gmail.com>
parent: Michael Moore <michaeljmoore@gmail.com>
0 siblings, 0 replies; 2+ messages in thread
From: Pavel Stehule @ 2016-01-19 18:09 UTC (permalink / raw)
To: Michael Moore <michaeljmoore@gmail.com>; +Cc: pgsql-sql
2016-01-15 21:24 GMT+01:00 Michael Moore <michaeljmoore@gmail.com>:
> This is ALMOST what I want:
> select json_strip_nulls ('[{ "f1":1 , "f2":null , "f3":"NULL" , "f4":""
> }]');
> the result is:
> "[{"f1":1,"f3":"NULL","f4":""}]"
>
> As you can see, the "f2" object has been removed. I would *also* like to
> remove the f3 and f4 objects.
>
> I realize I won't be able to use the json_strip_nulls function to do this.
> I could brute force it by doing "json to array" then looping through the
> array and picking only the objects I want, and then using the chosen
> objects to build an new JSON document.
>
> I suspect there is a more elegant way to accomplish the same objective.
> Ideas?
>
if you generate JSON from zero, then replace "" and "NULL" by NULL before
jsonification.
Pavel
>
> PS. It would be great to have a json_strip_values (json, array) where
> array contains the list of values you want removed.
>
^ permalink raw reply [nested|flat] 2+ messages in thread
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2016-01-15 20:24 remove null values from json Michael Moore <michaeljmoore@gmail.com>
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