Re: Better way to sort a JSONB array?

On Mon, Aug 7, 2017 at 1:13 PM, Michael Moore <michaeljmoore(at)gmail(dot)com>
wrote:

> This works, but surely there is a better way to do it:
>

What do you mean by "better"?
​

>
> select jsonb_agg(row_to_json(alias)) from
> (Select * from jsonb_populate_recordset(null::tx_portal,
> json_table2) order by portal_name) alias
> into
> json_table2;
>
> It sorts the json_table2 array in "portal_name" order.
>

​The only other possibility would be:

CREATE TABLE json_table2 AS
select jsonb_agg(row_to_json(alias) order by portal_name) from
(select * from jsonb_populate_recordset(...)) alias​;

i.e., move the order by into the aggregate; I prefer CREATE TABLE AS over
SELECT INTO ...

I don't know why you are thinking there is a better way...you are doing two
distinct actions here and you have two invocations of select...seems like
the minimal possible number of sub-statements to me. No one has written a
c-language function for core that provides a more friendly interface to
this. Looking at your query doing so using dynamic SQL within a pl/pgsql
function would seem reasonably easy.

I would suggest not using "json_table2" as both the name of the input
variable and the target table name - it can be confusing to follow when you
overload names like that.

David J.