Book Image

PostgreSQL Development Essentials

By : Manpreet Kaur, Baji Shaik
Book Image

PostgreSQL Development Essentials

By: Manpreet Kaur, Baji Shaik

Overview of this book

PostgreSQL is the most advanced open source database in the world. It is easy to install, configure, and maintain by following the documentation; however, it’s difficult to develop applications using programming languages and design databases accordingly. This book is what you need to get the most out of PostgreSQL You will begin with advanced SQL topics such as views, materialized views, and cursors, and learn about performing data type conversions. You will then perform trigger operations and use trigger functions in PostgreSQL. Next we walk through data modeling, normalization concepts, and the effect of transactions and locking on the database. The next half of the book covers the types of indexes, constrains, and the concepts of table partitioning, as well as the different mechanisms and approaches available to write efficient queries or code. Later, we explore PostgreSQL Extensions and Large Object Support in PostgreSQL. Finally, you will perform database operations in PostgreSQL using PHP and Java. By the end of this book, you will have mastered all the aspects of PostgreSQL development. You will be able to build efficient enterprise-grade applications with PostgreSQL by making use of these concepts
Table of Contents (17 chapters)
PostgreSQL Development Essentials
About the Authors
About the Reviewers

Defining transactions

In the previous chapters, we mentioned that we should try and write all the database changes with a single declarative statement. However, when it comes to reality, there comes a time when you cannot write everything to a database using one single SQL statement. This doesn't mean it will be just one single SQL statement; there might be multiple statements that will update the database correctly. If, by chance, any problem is encountered in the statement or a group of statements, then none of the database changes should be written. In other words, you will require the SQL statements to work as an individual unit and execute tasks sequentially in a way that allows the changes to be reversed and hides uncommitted changes from other processes. In this case, either all of the statements should be executing successfully or none of them should be executing.

A real-world example can be taken from the banking domain, where all transactions are recorded in debit and credit. So...