Book Image

Practical DevOps

By : joakim verona
Book Image

Practical DevOps

By: joakim verona

Overview of this book

DevOps is a practical field that focuses on delivering business value as efficiently as possible. DevOps encompasses all the flows from code through testing environments to production environments. It stresses the cooperation between different roles, and how they can work together more closely, as the roots of the word imply—Development and Operations. After a quick refresher to DevOps and continuous delivery, we quickly move on to looking at how DevOps affects architecture. You'll create a sample enterprise Java application that you’ll continue to work with through the remaining chapters. Following this, we explore various code storage and build server options. You will then learn how to perform code testing with a few tools and deploy your test successfully. Next, you will learn how to monitor code for any anomalies and make sure it’s running properly. Finally, you will discover how to handle logs and keep track of the issues that affect processes
Table of Contents (17 chapters)
Practical DevOps
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Handling database migrations


Handling changes in a relational database requires special consideration.

A relational database stores both data and the structure of the data. Upgrading a database schema offers other challenges then the ones present when upgrading program binaries. Usually, when we upgrade an application binary, we stop the application, upgrade it, and then start it again. We don't really bother about the application state. That is handled outside of the application.

When upgrading databases, we do need to consider state, because a database contains comparatively little logic and structure, but contains much state.

In order to describe a database structure change, we issue a command to change the structure.

The database structures before and after a change is applied should be seen as different versions of the database. How do we keep track of database versions?

Note

Liquibase is a database migration system that, at its core, uses a tried and tested method. There are many systems...