The following bug has been logged on the website:
Bug reference: 13917
Logged by: dante vitale
Email address: dv(at)unlimitedsoftware(dot)it
PostgreSQL version: 9.5.0
Operating system: centos 6
Description:
an INSERT ... ON CONFLICT DO NOTHING statement doesn't twork if unique index
on duplicated field is created without "where" clause. In case of co called
"partial index" the duplicate key exception rises.