Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases now! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
PostgreSQL Administration Cookbook, 9.5/9.6 Edition

You're reading from   PostgreSQL Administration Cookbook, 9.5/9.6 Edition Effective database management for administrators

Arrow left icon
Product type Paperback
Published in Apr 2017
Publisher
ISBN-13 9781785883187
Length 556 pages
Edition 3rd Edition
Languages
Arrow right icon
Authors (4):
Arrow left icon
Gianni Ciolli Gianni Ciolli
Author Profile Icon Gianni Ciolli
Gianni Ciolli
Hannu Krosing Hannu Krosing
Author Profile Icon Hannu Krosing
Hannu Krosing
Gabriele Bartolini Gabriele Bartolini
Author Profile Icon Gabriele Bartolini
Gabriele Bartolini
Simon Riggs Simon Riggs
Author Profile Icon Simon Riggs
Simon Riggs
Arrow right icon
View More author details
Toc

Table of Contents (13) Chapters Close

Preface 1. First Steps FREE CHAPTER 2. Exploring the Database 3. Configuration 4. Server Control 5. Tables and Data 6. Security 7. Database Administration 8. Monitoring and Diagnosis 9. Regular Maintenance 10. Performance and Concurrency 11. Backup and Recovery 12. Replication and Upgrades

Discovering why a query is not using an index

This recipe explains what to do if you think your query should use an index, yet it does not.

There can be several reasons for this, but most often, the reason is that the optimizer believes that, based on the available distribution statistics, it is cheaper and faster to use a query plan that does not use that specific index.

Getting ready

First, check that your index exists and ensure that the table has been analyzed. If there is any doubt, rerun it to be sure:

postgres=# ANALYZE;
ANALYZE

How to do it...

Force index usage...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime