Book Image

PostgreSQL High Performance Cookbook

By : Chitij Chauhan, Dinesh Kumar
Book Image

PostgreSQL High Performance Cookbook

By: Chitij Chauhan, Dinesh Kumar

Overview of this book

PostgreSQL is one of the most powerful and easy to use database management systems. It has strong support from the community and is being actively developed with a new release every year. PostgreSQL supports the most advanced features included in SQL standards. It also provides NoSQL capabilities and very rich data types and extensions. All of this makes PostgreSQL a very attractive solution in software systems. If you run a database, you want it to perform well and you want to be able to secure it. As the world’s most advanced open source database, PostgreSQL has unique built-in ways to achieve these goals. This book will show you a multitude of ways to enhance your database’s performance and give you insights into measuring and optimizing a PostgreSQL database to achieve better performance. This book is your one-stop guide to elevate your PostgreSQL knowledge to the next level. First, you’ll get familiarized with essential developer/administrator concepts such as load balancing, connection pooling, and distributing connections to multiple nodes. Next, you will explore memory optimization techniques before exploring the security controls offered by PostgreSQL. Then, you will move on to the essential database/server monitoring and replication strategies with PostgreSQL. Finally, you will learn about query processing algorithms.
Table of Contents (19 chapters)
PostgreSQL High Performance Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Comparing indexed scans and sequential scans


In this recipe, let's compare the index and sequential scan behaviors using the inotifywait utility command, which will print a message when the mentioned event occurs on the given files.

Getting ready

inotify tools is a module that we can download using either the apt-get or yum command in the corresponding Linux distribution. This contrib module is developed based on the inotify kernel API, which provides some kind of audit mechanism over the filesystem. To compare the index and sequential scan behavior, let's audit the relation and index physical file while executing the SQL queries.

How to do it...

Let's get the locations of index and relation physical files location using the pg_relation_filepath function, as follows:

benchmarksql=# SELECT pg_relation_filepath('pric_idx'); 
pg_relation_filepath  
---------------------- 
base/12439/16545 
(1 row) 
 
benchmarksql=# SELECT pg_relation_filepath('bmsql_item'); 
pg_relation_filepath  
-----------...