Book Image

Learning PostgreSQL

Book Image

Learning PostgreSQL

Overview of this book

PostgreSQL is one of the most powerful and easy to use database management systems. It supports the most advanced features included in SQL standards. The book starts with the introduction of relational databases with PostegreSQL. It then moves on to covering data definition language (DDL) with emphasis on PostgreSQL and common DDL commands supported by ANSI SQL. You will then learn the data manipulation language (DML), and advanced topics like locking and multi version concurrency control (MVCC). This will give you a very robust background to tune and troubleshoot your application. The book then covers the implementation of data models in the database such as creating tables, setting up integrity constraints, building indexes, defining views and other schema objects. Next, it will give you an overview about the NoSQL capabilities of PostgreSQL along with Hstore, XML, Json and arrays. Finally by the end of the book, you'll learn to use the JDBC driver and manipulate data objects in the Hibernate framework.
Table of Contents (21 chapters)
Learning PostgreSQL
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Chapter 5. SQL Language

Structured Query Language (SQL) is used to set up the structure of the database, to manipulate the data in the database and to query the database. This chapter will be dedicated to the Data Manipulation Language (DML).

After reading this chapter, you will understand the concept of SQL and the logic of SQL statements. You will be able to write your own SQL queries and manipulate the data using this language.

The complete reference of SQL can be found in the official PostgreSQL documentation at http://www.postgresql.org/docs/current/static/sql.html.

So, the topics we are going to cover in this chapter are as follows:

  • SQL fundamentals

  • Lexical structure

  • Select

  • Update

  • Delete

Code examples in this chapter are based on the car portal database described in the previous chapters. The scripts to create the database and fill it with data can be found in the attached media in the Chapter 5 folder. They are called schema.sql and data.sql.

All the code examples of this chapter can be...