SQL in easy steps, 4th edition

Mike McGrath

• Editore: In Easy Steps Limited
• Anno: 2020
• ISBN:
  9781840789201
• Argomento: Computer Science
• Categoria: Programming in SQL

SQL (Structured Query Language) is THE standard language used world-wide for database communication on all popular database software. It allows the storage and manipulation of data both on Windows platforms and on Unix-based platforms, such as Linux.

SQL in easy steps, 4th edition begins by explaining how to download and install the free MySQL database server on both Windows and Linux platforms. This allows you to establish an environment in which to develop and administer your own databases. This book makes no assumption that you will have previous knowledge of any programming or scripting language so it's ideal for the newcomer to SQL. Each chapter builds your knowledge of executing database queries. The book contains exciting chapters on how to selectively extract data from within one, or more, databases and there are complete examples that illustrate each aspect of SQL. By the end of this book you will have gained a sound understanding of the Structured Query Language and be able to write your own SQL scripts to insert, extract, and manipulate data.

SQL in easy steps, 4th edition has an easy-to-follow style that will appeal to anyone who wants to begin using databases. It is suitable for those with little or no experience of SQL. This book will appeal to all who need a fundamental understanding of database administration with SQL:

• Web developers wanting to add database interaction to their web sites
• Programmers wanting to add SQL to their skills set
• Hobbyists who want to begin creating SQL scripts for upload to their own ISP
• Students or those seeking a career in computing.

Free, downloadable source code is available from our website so you can check the code against your own work, and get started straight away!

1

Introducing SQL

Welcome to the exciting world of the Structured Query Language (SQL). This chapter describes how to install a free SQL database server on your system.

What is SQL?

Making MySQL queries

Installing MySQL on Windows

Installing MySQL on Linux

Adding an ODBC connector

Using Microsoft Query tool

Summary

What is SQL?

The Structured Query Language (SQL) is a language designed specifically for communicating with databases. Today SQL is the industry-wide standard language used by most database systems.

A programming language (pronounced either “S-Q-L” or “sequel”) designed to manage database data.

Databases allow collections of data to be stored in an organized manner – in the same way that data can be stored in an organized way inside files within a filing cabinet. Most modern DataBase Management Systems (DBMSs) store data in related tables, so are called Relational DBMS (RDBMS). The data stored inside databases can be examined and manipulated by SQL commands.

SQL commands are known as “queries” and utilize special keywords that can be used both to add data to a database, or extract details of data contained within a database. There are not many keywords so SQL is simple to understand but, despite its apparent simplicity, is a powerful language. Clever use of its language components enable complex sophisticated database operations to be performed.

The evolution of SQL

The model for the basis of SQL was defined back in 1970 by Dr. E. F. Todd, a researcher for IBM, in a paper entitled “A Relational Model of Data for Large Shared Data Banks”. This article generated a great deal of interest in the feasibility of producing a practical commercial application of such a system.

IBM really began to develop these ideas in 1974 when they started the System/R project which eventually created the Structured English Query Language (SEQUEL). This was rewritten in 1976 to include multi-table and multi-user features and was renamed SQL in 1978. During this time other software companies had begun working on database systems based upon the SQL model. Most notable of these were Oracle, Sybase and Ingres (from the University of California’s Berkeley Ingres project). The first to be released commercially was Oracle in 1979. IBM released improved database products named SQL/DS in 1982 and DB2 in 1983.

Modern versions of Oracle, Sybase, Ingres and DB2 DBMS are available today and are in widespread use around the world.

Standardization of SQL

In ord...