On Thu, 19 Aug 2021, David G. Johnston wrote:
> I thought you said (p.person_nbr, c.contact_date) is already unique?
David,
Yes, that's the PK for the contacts table. I'm still unsure what needs to be
explicitly included in a query. Quite often I leave out a column and
postgres tells me it needs to be included in order by or group by.
Rich
