Book Image

Mastering PostgreSQL 9.6

By : Hans-Jürgen Schönig
Book Image

Mastering PostgreSQL 9.6

By: Hans-Jürgen Schönig

Overview of this book

PostgreSQL is an open source database used for handling large datasets (Big Data) and as a JSON document database. It also has applications in the software and web domains. This book will enable you to build better PostgreSQL applications and administer databases more efficiently. We begin by explaining the advanced database design concepts in PostgreSQL 9.6, along with indexing and query optimization. You will also see how to work with event triggers and perform concurrent transactions and table partitioning, along with exploring SQL and server tuning. We will walk you through implementing advanced administrative tasks such as server maintenance and monitoring, replication, recovery and high availability, and much more. You will understand the common and not-so-common troubleshooting problems and how you can overcome them. By the end of this book, you will have an expert-level command of the advanced database functionalities and will be able to implement advanced administrative tasks with PostgreSQL.
Table of Contents (14 chapters)
Free Chapter
PostgreSQL Overview

Upgrading to synchronous replication

So far, asynchronous replication has been covered in reasonable detail. However, asynchronous replication means that a commit on the slave is allowed to happen after the commit on the master. If a master crashes, data that has not made it to the slave yet might be lost even if replication is around.

Synchronous replication is here to solve the problem: if PostgreSQL replicates synchronously, a commit has to be flushed to disk by at least one replica in order to go through on the master. Therefore, synchronous replication basically reduces the odds of data loss quite substantially.

In PostgreSQL, configuring synchronous replication is easy. Basically, just two things have to be done:

  • Adjust the synchronous_standby_names setting in the postgresql.conf file on the master
  • Add an application_name setting to the primary_conninfo parameter in the recovery.conf file in the replica