Databáze
PostgreSQL replikace
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.