Hi Rob:
On Mon, 10 Apr 2023 at 04:16, Rob Sargent <robjsargent@gmail.com> wrote:
> > An UPSERT checks whether a row exists, if so, it does an update, if not it does an insert. This is the literal
definition.
> This the part that's always eluded me: How does the client, the
> UPSERTer, come to hold an id and not know whether or not it's already in
> the database.
This is extremely easy to do if you have natural instead of surrogate keys.
I work in telephony, upserting the last incoming call timestamp for a
phone number will be exactly that.
Francisco Olarte.