Re: JSON for PG 9.2 - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: JSON for PG 9.2
Date
Msg-id 4F8C2859.6050203@dunslane.net
Whole thread Raw
In response to Re: JSON for PG 9.2  (Hannu Krosing <hannu@krosing.net>)
Responses Re: JSON for PG 9.2
Re: JSON for PG 9.2
List pgsql-hackers

On 04/16/2012 09:34 AM, Hannu Krosing wrote:
>> based on Abhijit's feeling and some discussion offline, the consensus
>> seems to be to remove query_to_json.
> The only comment I have here is that query_to_json could have been
> replaced with json_agg, so thet you don't need to do double-buffering
> for the results of array(<yourquery>) call in
>
> SELECT array_to_json(array(<yourquery>));
>
> Or is there some other way to avoid it except to wrap row_to_json()
> calls in own aggregate function which adds enclosing brackets and comma
> separator ( like this : '['<row1>[,<rowN>]']' ?
>
>

The way I usually write this is:
    select array_to_json(array_agg(q))    from (<yourquery>) q;

It's a pity you didn't make this comment back in January when we were 
talking about this. I think it's too late now in this release cycle to 
be talking about adding the aggregate function.

cheers

andrew


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