6 of the Best Free SQL Books

1. Practical PostgreSQL

Practical PostgreSQL is a comprehensive book that shows the reader how to compile PostgreSQL from source, create a database, and configure PostgreSQL to accept client-server connections. It also covers the many advanced features, such as transactions, versioning, replication, and referential integrity that enable developers and DBAs to use PostgreSQL for serious business applications.

The thorough introduction to PostgreSQL's PL/pgSQL programming language explains how you can use this very useful but under-documented feature to develop stored procedures and triggers. The book includes a complete command reference, and database administrators will benefit from the chapters on user management, database maintenance, and backup & recovery. With Practical PostgreSQL, the reader will discover quickly why this open source database is a great open source alternative to proprietary products from Oracle, IBM, and Microsoft.

Chapters cover:

• Introduction and Installation
• Using PostgreSQL - cover understanding SQL, using SQL with PostgreSQL, operators and functions, PostgreSQL clients (psql and PgAccess), and advanced features
• Administrating PostgreSQL - authentication and encryption, database management, user and group management
• Programming with PostgreSQL - PL/pgSQL, JDBC, and LXP
• PostgreSQL Command Reference
• Appendixes: Multibyte Encoding Types, Backend Options for Postgres, Binary COPY Format, and Internal pyql Variables

2. SQL Performance Explained

SQL Performance Explained helps developers to improve database performance. The focus is on SQL; it covers all major SQL databases without getting lost in the details of any one specific product.

Starting with the basics of indexing and the WHERE clause, SQL Performance Explained guides developers through all parts of an SQL statement and explains the pitfalls of object-relational mapping (ORM) tools like Hibernate.

Topics covered include:

• Anatomy of an Index - the fundamental structure of an index
• The Where Clause - explains all aspects of the where clause, from very simple single column lookups to complex clauses for ranges and special cases such as LIKE
• Performance and Scalability - looks at Performance and Scalability
• The Join Operation - an explanation of how to use indexes to perform a fast table join
• Clustering Data - the difference between selecting a single column and all columns
• Sorting and Grouping - even order by and group by can use indexes
• Partial Results - explains how to benefit from a "pipelined" execution if you don’t need the full result set
• Insert, Delete and Update
• Appendices: Execution Plans, Myth Directory, and Example Schema

3. A Primer on SQL

A Primer on SQL is a fairly short ebook teaching the basics of SQL. The author assumes that the reader has no previous experience of SQL.

While the examples and text use Ingres as the database management system, the code should work correctly on any SQL compliant database. Since this text deals largely with teaching SQL in a product independent manner, rather than the teaching of Ingres per se, details with respect to installation and specific operations of the product is kept to a minimum.

Chapters cover:

• An Introduction to SQL
• Getting your Database ready - covers the basic of creating a database, inserting data, and writing a query
• Constraints - a rule that you apply or abide by while doing SQL operations. This chapter examines selective fields INSERT, primary key constraint, unique key constraint, and the differences between a primary key and a unique key
• Operations on Tables - drop tables, create new tables from existing tables, modify tables, verifying the result in Ingres and other database systems
• Writing Basic Queries - a query is a SQL statement that is used to extract a subset of data from your database and presents it in a readable format
• Manipulating Data - looks at the Data Manipulation Language (DML) part of SQL which is used to make changes to the data inside a relational database
• Organizing your Data - covers normalization, atomicity, repeating groups, and splitting the table
• Doing more with Queries - more examples of how we can modify SELECT statements; counting the records in a table, column aliases, and using the LIKE operator
• Aggregation and Grouping - an aggregate function is used to compute summarization information from a table or tables. Looks at using DISTINCT with COUNT, using MIN to find minimum values, grouping data with the GROUP BY clause of a SELECT query, and the HAVING clause
• Understanding Joins - a join operation allows you to retrieve data from multiple tables in a single SELECT query

This material is licensed under the Open Publication License, v1.0 or later.