Learning PHP, MySQL, JavaScript, and CSS, 2nd Edition

MySQL Basics

A database is a structured collection of records or data stored in a computer system and organized in such a way that it can be searched quickly and information can be retrieved rapidly.

The SQL in MySQL stands for Structured Query Language. This language is loosely based on English and is also used on other databases, such as Oracle and Microsoft SQL Server. It is designed to allow simple requests from a database via commands such as:

SELECT title FROM publications WHERE author = 'Charles Dickens';

A MySQL database contains one or more tables, each of which contains records or rows. Within these rows are various columns or fields that contain the data itself. Table 8-1 shows the contents of an example database of five publications detailing the author, title, type, and year of publication.

Table 8-1. Example of a simple database

Author	Title	Type	Year
Mark Twain	The Adventures of Tom Sawyer	Fiction	1876
Jane Austen	Pride and Prejudice	Fiction	1811
Charles Darwin	The Origin of Species	Non-Fiction	1856
Charles Dickens	The Old Curiosity Shop	Fiction	1841
William Shakespeare	Romeo and Juliet	Play	1594

Each row in the table is the same as a row in a MySQL table, and each element within a row is the same as a MySQL field.

To uniquely identify this database, I’ll refer to it as the publications database in the examples that follow. And, as you will have observed, all these publications are considered to be classics of literature, so I’ll call the table within the ...