Postgres and Open Source Experts

24x7x365 since 1997


Professional Postgres and Open Source support

Command Prompt, Inc., is the oldest Postgres Company in North America and one of the oldest Open Source firms still operating today. We serve our clients with best in class expertise and professionalism. You can read more about support and services here:

You have landed at the largest single source of Postgres education blogs in the world. At Command Prompt, we believe deeply that the education of the community is critical to the continued success of Postgres and related technologies. We hope you find content you are looking for and don't hesitate to Contact us today for all your Postgres and Open Source consulting and support needs.

pglogical Rediscovered: A Fresh Approach to Logical Replication for Ultra-high Availability

by Hari Kiran

August 22, 2023

Data replication is an essential aspect of modern database management systems, ensuring data availability, fault tolerance, and scalability. In the PostgreSQL world, a groundbreaking extension called Spock has emerged, transforming the way multi-active replication is handled. Spock, based on the pglogical logical replication tool, brings in a host of new features, including conflict resolution and avoidance, asynchronous replication, and more. In this blog post, …

What is PostgreSQL?

PostgreSQL is the only Open Source database in the world that focuses on correctness first and extends that correctness to features such as NoSQL (JSON), ASYNC/SYNC Binary and Logical Replication. PostgreSQL also has features such as Horizontal partitioning, Stored Procedures and abilities to use replication to other legacy database systems such as MSSQL and Oracle.

PostgreSQL Indexes: B-Tree

In older versions of PostgreSQL, a B-tree index only contained pointers to the heap (table) of where a particular set of data could be accessed. This can cause performance issues because we first need to scan the index and then retrieve the data from the table. While Index scans are relatively cheap due to how they store data, table scans can be very expensive because the data can be at any place within the table. Though current enterprise methods of storage have alleviated much of this (SSD/NVME) performance impact, it still exists as we need to search for the data twice.