Book Image

Learning PostgreSQL 10 - Second Edition

Book Image

Learning PostgreSQL 10 - Second Edition

Overview of this book

PostgreSQL is one of the most popular open source databases in the world, supporting the most advanced features included in SQL standards. This book will familiarize you with the latest features released in PostgreSQL 10. We’ll start with a thorough introduction to PostgreSQL and the new features introduced in PostgreSQL 10. We’ll cover the Data Definition Language (DDL) with an emphasis on PostgreSQL, and the common DDL commands supported by ANSI SQL. You’ll learn to create tables, define integrity constraints, build indexes, and set up views and other schema objects. Moving on, we’ll cover the concepts of Data Manipulation Language (DML) and PostgreSQL server-side programming capabilities using PL/pgSQL. We’ll also explore the NoSQL capabilities of PostgreSQL and connect to your PostgreSQL database to manipulate data objects. By the end of this book, you’ll have a thorough understanding of the basics of PostgreSQL 10 and will have the necessary skills to build efficient database solutions.
Table of Contents (23 chapters)
Title Page
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Python DB API 2.0


PostgreSQL is not the only relational database and of course it is not the only one you can use with Python. There is an API in Python that is designed to unify the way applications work with databases. It is called the Python Database API. By the time this book was written, it already had the second specification, defined in the Python Enhancement Proposal (PEP) 249. The specification of the Python DB API 2.0 is available at https://www.python.org/dev/peps/pep-0249/.

The API defines the following objects that are used when connecting to a database and interacting with it:

  • connection: This implements the logic of connecting to the database server, authenticating and managing transactions. A connection is created by calling the connect() function with a number of parameters that can differ depending on the database and the driver that is used.
  • cursor: This represents a cursor in the database. It is an object that is used to manage the context of execution of a SQL command....