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Thread: How to select values in a JSON type of column?

How to select values in a JSON type of column?

From
Snjezana Frketic
Date:
Hi!

I have a column called targeting in a table called campaigns .
The column looks like
{
   "targets": [
     {
       "audienceSegments": [
         {
           "includes": [
             {
               "consumer": "selection",
               "segments": {
                 "allOf": [
                   {
                     "provider": "a",
                     "ids": [
                       {
                         "id": "110418"
                       },
                       {
                         "id": "110430"
                       },
                       {
                         "id": "110433"
                       }
                     ]
                   }
                 ]
               }
             }
           ],
           "excludes": [
             {
               "consumer": "selection",
               "segments": {
                 "allOf": [
                   {
                     "provider": "a",
                     "ids": [
                       {
                         "id": "109776"
                       }
                     ]
                   }
                 ]
               }
             }
           ]
         }
       ]
     }
   ]
 }
and I need to select all the ids in includes.
Currently, I am doing it like this 

SELECT targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;  

and that works, but, I don’t want to have a fixed path because positions could change like 0 could become 1, includes and excludes could change positions, allOf  could be anyOf etc.
Any idea of how to always select ids in includes no matter the changes?

Thank you!
Anna

Re: How to select values in a JSON type of column?

From
"David G. Johnston"
Date:

On Wednesday, November 18, 2020, Snjezana Frketic <frketic.snjezana@gmail.com> wrote:


SELECT targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;  

and that works, but, I don’t want to have a fixed path because positions could change like 0 could become 1, includes and excludes could change positions, allOf  could be anyOf etc.
Any idea of how to always select ids in includes no matter the changes?

  Maybe it can be done using json path:


David J.

Re: How to select values in a JSON type of column?

From
Snjezana Frketic
Date:
I looked at it yesterday, but I couldn't figure it out because my JSON is more nested and I got lost going down the path. 


On Wed, 18 Nov 2020 at 15:40, David G. Johnston <david.g.johnston@gmail.com> wrote:

On Wednesday, November 18, 2020, Snjezana Frketic <frketic.snjezana@gmail.com> wrote:


SELECT targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;  

and that works, but, I don’t want to have a fixed path because positions could change like 0 could become 1, includes and excludes could change positions, allOf  could be anyOf etc.
Any idea of how to always select ids in includes no matter the changes?

  Maybe it can be done using json path:


David J.

Re: How to select values in a JSON type of column?

From
Thomas Kellerer
Date:
Snjezana Frketic schrieb am 18.11.2020 um 11:29:
> I have a column called |targeting| in a table called |campaigns| .
> [...]
> and I need to select all the |ids| in |includes|.
> Currently, I am doing it like this 
>
> SELECT |targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;|  
>

If you are on Postgres 12 or later, this can be done using jsonb_path_query_array:

  select jsonb_path_query_array(targeting, '$.targets[*].*.includes.**.ids.id')
  from campaigns


Online example: https://dbfiddle.uk/?rdbms=postgres_12&fiddle=ee7f6e73055ffb3a98fcfd3d86763e35

Thomas

Re: How to select values in a JSON type of column?

From
Snjezana Frketic
Date:
I actually have version 9.3.17 😬


On Wed, 18 Nov 2020 at 15:55, Thomas Kellerer <shammat@gmx.net> wrote:
Snjezana Frketic schrieb am 18.11.2020 um 11:29:
> I have a column called |targeting| in a table called |campaigns| .
> [...]
> and I need to select all the |ids| in |includes|.
> Currently, I am doing it like this 
>
> SELECT |targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;|  
>

If you are on Postgres 12 or later, this can be done using jsonb_path_query_array:

  select jsonb_path_query_array(targeting, '$.targets[*].*.includes.**.ids.id')
  from campaigns


Online example: https://dbfiddle.uk/?rdbms=postgres_12&fiddle=ee7f6e73055ffb3a98fcfd3d86763e35

Thomas


Re: How to select values in a JSON type of column?

From
Snjezana Frketic
Date:
Unfortunately, I also can not update my version :) 

On Wed, 18 Nov 2020 at 17:00, Snjezana Frketic <frketic.snjezana@gmail.com> wrote:
I actually have version 9.3.17 😬


On Wed, 18 Nov 2020 at 15:55, Thomas Kellerer <shammat@gmx.net> wrote:
Snjezana Frketic schrieb am 18.11.2020 um 11:29:
> I have a column called |targeting| in a table called |campaigns| .
> [...]
> and I need to select all the |ids| in |includes|.
> Currently, I am doing it like this 
>
> SELECT |targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;|  
>

If you are on Postgres 12 or later, this can be done using jsonb_path_query_array:

  select jsonb_path_query_array(targeting, '$.targets[*].*.includes.**.ids.id')
  from campaigns


Online example: https://dbfiddle.uk/?rdbms=postgres_12&fiddle=ee7f6e73055ffb3a98fcfd3d86763e35

Thomas


Re: How to select values in a JSON type of column?

From
"David G. Johnston"
Date:
On Wed, Nov 18, 2020 at 9:23 AM Snjezana Frketic <frketic.snjezana@gmail.com> wrote:
Unfortunately, I also can not update my version :) 

Then probably the answer to your original question is no :)

There are possibly other ways to make something that works but if you aren't willing to upgrade off of a discontinued version, onto one which has a perfectly usable solution, then my interest in pondering a work-around is near zero.

David J.

Re: How to select values in a JSON type of column?

From
Snjezana Frketic
Date:
Fair point. 
Appreciate your help nevertheless :) 


On Wed, 18 Nov 2020 at 17:30, David G. Johnston <david.g.johnston@gmail.com> wrote:
On Wed, Nov 18, 2020 at 9:23 AM Snjezana Frketic <frketic.snjezana@gmail.com> wrote:
Unfortunately, I also can not update my version :) 

Then probably the answer to your original question is no :)

There are possibly other ways to make something that works but if you aren't willing to upgrade off of a discontinued version, onto one which has a perfectly usable solution, then my interest in pondering a work-around is near zero.

David J.

Re: How to select values in a JSON type of column?

From
Thomas Kellerer
Date:
Snjezana Frketic schrieb am 18.11.2020 um 17:00:
> I actually have version 9.3.17 😬
>
>
> On Wed, 18 Nov 2020 at 15:55, Thomas Kellerer <shammat@gmx.net <mailto:shammat@gmx.net>> wrote:
>
>     Snjezana Frketic schrieb am 18.11.2020 um 11:29:
>      > I have a column called |targeting| in a table called |campaigns| .
>      > [...]
>      > and I need to select all the |ids| in |includes|.
>      > Currently, I am doing it like this
>      >
>      > SELECT |targeting#>'{targets,0,audienceSegments,0,includes,0,segments,allOf,0,ids}'FROM campaigns;|
>      >
>
>     If you are on Postgres 12 or later, this can be done using jsonb_path_query_array:
>
>        select jsonb_path_query_array(targeting, '$.targets[*].*.includes.**.ids.id <http://ids.id>')
>        from campaigns

If you are limited to an unsupported version, you need to go down the hierarchy manually:

select t.ids
from campaigns c
    cross join lateral (
      select array_agg(s2.seg2 ->> 'id') as ids
      from json_array_elements(c.targeting -> 'targets') as t(target)
        cross join json_array_elements(t.target -> 'audienceSegments') as a(aud)
        cross join json_array_elements(a.aud -> 'includes') as i(include)
        cross join json_array_elements(i.include #> '{segments,allOf}') as s(seg)
        cross join json_array_elements(s.seg -> 'ids') as s2(seg2)
    ) t