Materialize data from cache table to production table [PostgreSQL]
The "best" solution according to the criteria you've laid out so far would just be to insert into the production table.
...unless there's actually something extremely relevant you're not telling us
I am trying to find the best solution (perfomance/easy code) for the following situation:
Considering a database system with two tables, A (production table) and A'(cache table):

Future rows are added first into A' table in order to not disturb the production one.
When a timer says go (at midnight, for example) rows from A' are incorporated to A.
Dealing with duplicates, inexistent rows, etc have to be considerated. 

I've been reading some about Materialized Views, Triggers, etc. The problem is that I should not introduce so much noise in the production table because is the reference table for a server (a PowerDNS server in fact).
So, what do you guys make of it? Should I better use triggers, MV, or programatically outside of the database?? (I'm using python, BTW)
Thanks in advance for helping me.