Database on Nikita Ryanov

PostgreSQL: Log shipping Replication

Wed, 04 Jan 2023 22:50:00 +0300

Prerequisite

All examples assume that postgresql is already installed on your machine. Also, all examples are created using PostgreSQL 14.1 on aarch64-apple-darwin20.6.0, compiled by Apple clang version 13.0.0 (clang-1300.0.29.3), 64-bit.

Log shipping replication

Log shipping replication (i will use a short name for it LSR) is another one method to physically replicate data between multiple database clusters. As name says this method is about to replicate data through WAL-files (segment) which is transferred between instances. This is probably the most simple and straightforward method for data replication, but this simplicity comes with price and compromises which also should be accounted.

PostgreSQL: Streaming Replication

Thu, 10 Feb 2022 22:50:00 +0300

Prerequisite

Streaming replication

Streaming replication is a built-in mechanism in PostgreSQL to replicate data between multiple servers. It is a low-level replication mechanism as it streams WAL data from primary server to the replica through the physical replication slot, so it is highly recommended to replicate data between servers using similar PostgreSQL major version (minor versions could be different). Also, it is a good idea to have equal servers in terms of server configuration such as CPU, RAM and Disks, especially if you consider to promote replica to master if primary server goes down.

PostgreSQL: Logical Replication

Fri, 04 Feb 2022 22:50:00 +0300

Prerequisite

Logical replication

Logical replication is another method to replicate data between multiple nodes. This replication uses publish-subscribe model. Each publisher may have multiple subscribers and each subscriber can subscribe to multiple publisher. Also, each subscriber may be a publisher for another node which make it possible to create a cascading replication.