PGConf.Russia 2023

There is set of Ansible roles for any Postgres configuration: a standalone instance; a streaming replica; patroni+etcd; stolon+etcd; patroni+consul; stolon+consul. In this talk, we will discuss why using this set of Ansible roles is better than other solutions.

The following topics will be covered as part of the presentation:

• Architecture of logical replication
• Publisher introduction
• Subscriber introduction
• Data syncronization introduction
• Logical decoding
• Replication slot
• output plugin

The importance of sharding is now colossal. The size of today's databases exceeds 100 terabytes, scaling up vertically, and adding replicas containing a complete physical copy of the database is becoming difficult, especially when computational resources are scarce. Database sharding is a way to scale horizontally by partitioning data between compute nodes that are independent of each other.

In the PostgreSQL world, there are well-known scaling tools - CitusDB, and Greenplum - as well as new generation solutions - Cockroach DB, Yugabyte DB, SPQR, and Shardman.

In this talk, we will discuss the difference between these implementations, the advantages, and disadvantages of these solutions, examine the current state of implementation of sharding in vanilla PostgreSQL, and also touch on another important topic - providing data integrity and consistency guarantees across a distributed cluster.