Sorry for the delay - used to getting replied-to-all on messages I send but you didn't and I didn't notice the response until now.
On Mon, Feb 29, 2016 at 4:03 AM, Rafal Pietrak <ra...@ztk-rp.eu> wrote: > > > > Partitioning and partial indexes both have considerable limitations that > > you might need to work around. That said normalization exists for a > > reason and having multiple "person" columns in a table is a form of > > duplication that if left presents just the problems you are seeing. > > > > I suspect your SSN should fit onto the message-person table. > > > > The following doesn't make sense - if the SSN is sender unique then > > there is no expectation that a receiver would not receive two messages > > with the same SSN from different senders. > > I don't get it. > > Of cource it's possible to receive two messages with the same SSN. > > By "sender unique" I mean, that every sender has full control of > whatever he/she wishes to use for SSN, provided that he/she does not > assign duplicates. It also means, that there is no relation between SSN > assigned by different senders and collisions *should* be expected unless > UNIQUE covers both THEM/SENDR and SSN. > > Thus: > > ALTER ... msgs_to_me ADD CONSTRINT them_uniq UNIQUE (THEM,SSN); > > Yeah, mental lapse on my part. David J.
