Book Image

PostgreSQL 14 Administration Cookbook

By : Simon Riggs, Gianni Ciolli
5 (1)
Book Image

PostgreSQL 14 Administration Cookbook

5 (1)
By: Simon Riggs, Gianni Ciolli

Overview of this book

PostgreSQL is a powerful, open-source database management system with an enviable reputation for high performance and stability. With many new features in its arsenal, PostgreSQL 14 allows you to scale up your PostgreSQL infrastructure. With this book, you'll take a step-by-step, recipe-based approach to effective PostgreSQL administration. This book will get you up and running with all the latest features of PostgreSQL 14 while helping you explore the entire database ecosystem. You’ll learn how to tackle a variety of problems and pain points you may face as a database administrator such as creating tables, managing views, improving performance, and securing your database. As you make progress, the book will draw attention to important topics such as monitoring roles, validating backups, regular maintenance, and recovery of your PostgreSQL 14 database. This will help you understand roles, ensuring high availability, concurrency, and replication. Along with updated recipes, this book touches upon important areas like using generated columns, TOAST compression, PostgreSQL on the cloud, and much more. By the end of this PostgreSQL book, you’ll have gained the knowledge you need to manage your PostgreSQL 14 database efficiently, both in the cloud and on-premise.
Table of Contents (14 chapters)

What is the server uptime?

You may be wondering, how long has it been since the server started?

For instance, you might want to verify that there was no server crash if your server is not monitored, or to see when the server was last restarted, for instance, to change the configuration. We will find this out by asking the database server.

How to do it…

Issue the following SQL from any interface:

postgres=# SELECT date_trunc('second', current_timestamp - pg_postmaster_start_time()) as uptime;

You should get the output as follows:

 2 days 02:48:04

How it works…

Postgres stores the server start time, so we can access it directly, as follows:

postgres=# SELECT pg_postmaster_start_time(); 
2021-10-01 19:37:41.389134+00

Then, we can write a SQL query to get the uptime, like this:

postgres=# SELECT current_timestamp - pg_postmaster_start_time(); 

Finally, we can apply some formatting:

postgres=# SELECT date_trunc('second', current_timestamp - pg_postmaster_start_time()) as uptime; 

See also

This is simple stuff. Further monitoring and statistics are covered in Chapter 8Monitoring and Diagnosis.