Re: Proposal: array_unique_agg() function

Hi

út 1. 3. 2022 v 14:39 odesílatel Aleksander Alekseev <
aleksander(at)timescale(dot)com> napsal:

> Hi hackers,
>
> I needed an aggregate function similar to array_agg() but which
> aggregates only unique values. As it turned out there is no convenient
> way of doing this. What I ended up doing instead was aggregating to
> JSONB keys and then converting a JSONB object to an array:
>
> SELECT array(select jsonb_object_keys(jsonb_object_agg(mycolumn, true)))
> FROM ...
>
> This works but doesn't seem to be the greatest user experience. I
> would like to submit a patch that adds array_unique_agg() function
> unless anyone has strong objections to this feature.
>

SELECT array_agg(DISTINCT ...) doesn't help?

Regards

Pavel

>
> --
> Best regards,
> Aleksander Alekseev
>
>
>