Replikace zajišťuje vysokou dostupnost a read scaling.

Streaming replikace¶

Primary: wal_level=replica, max_wal_senders=5¶

Replica:¶

pg_basebackup -h primary -U replicator -D /var/lib/postgresql/16/main -P

primary_conninfo=’host=primary user=replicator’¶

Logical replikace¶

– Primary CREATE PUBLICATION my_pub FOR TABLE users, orders; – Subscriber CREATE SUBSCRIPTION my_sub CONNECTION ‘host=primary dbname=mydb’ PUBLICATION my_pub;

Monitoring¶

SELECT client_addr, state, sent_lsn, replay_lsn FROM pg_stat_replication; SELECT now()-pg_last_xact_replay_timestamp() AS lag;

• Streaming — HA, read replicas, celá DB
• Logical — selective tables, cross-version

Replikace pro HA¶

Streaming pro HA, logical pro selektivní replikaci.