> From: Tatsuo Ishii [mailto:ishii@sraoss.co.jp] >> But pg_is_in_recovery() returns true even for a promoting standby. So >> you have to wait and retry to send pg_is_in_recovery() until it >> finishes the promotion to find out it is now a primary. I am not sure >> if backend out to be responsible for this process. If not, libpq would >> need to handle it but I doubt it would be possible. > > Yes, the application needs to retry connection attempts until success. That's not different from PgJDBC and other DBMSs.
I don't know what PgJDBC is doing, however I think libpq needs to do more than just retrying.
1) Try to find a node on which pg_is_in_recovery() returns false. If found, then we assume that is the primary. We also assume that other nodes are standbys. done.
2) If there's no node on which pg_is_in_recovery() returns false, then we need to retry until we find it. To not retry forever, there should be a timeout counter parameter.
