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)

Removing a user without dropping their data

When trying to drop a user who owns some tables or other database objects, you get the following error, and the user is not dropped:

testdb=# drop user bob;
ERROR:  role "bob" cannot be dropped because some objects depend on it
DETAIL:  owner of table bobstable
owner of sequence bobstable_id_seq

This recipe presents two solutions to this problem.

Getting ready

To modify users, you must either be a superuser or have the CREATEROLE privilege.

How to do it…

The easiest solution to this problem is to refrain from dropping the user and use the trick from the Temporarily preventing a user from connecting recipe to prevent the user from connecting:

pguser=# alter user bob nologin;

This has the added benefit of the original owner of the table being available later, if needed, for auditing or debugging purposes (Why is this table here? Who created it?).

Then, you can assign...