On Fri, Dec 5, 2014 at 1:01 AM, Anssi Kääriäinen
<anssi.kaariainen@thl.fi> wrote:
> If Django is going to use the INSERT ... ON CONFLICT UPDATE variant in
> Django for the existing save() method, then it needs to know if the
> result was an UPDATE or INSERT. If we are going to use this for other
> operations (for example bulk merge of rows to the database), it would be
> very convenient to have per-row updated/created information available so
> that we can fire the post_save signals for the rows. If we don't have
> that information available, it means we can't fire signals, and no
> signals means we can't use the bulk merge operation internally as we
> have to fire the signals where that happened before.
>
> Outside of Django there are likely similar reasons to want to know if
> the result of an operation was a creation of a new row. The reason could
> be creation of related row, doing some action in application layer, or
> just UI message telling "object created successfully" vs "object updated
> successfully".
It probably isn't ideal, but you'd at least be able to do something
with row level triggers in the absence of a standard way of directly
telling if an insert or update was performed.
--
Peter Geoghegan
