ZEND PHP 5 Certification STUDY GUIDE

146 ” Database Programming
These two forms are equivalent to each other— is the name of the new
database you want to create. As you can see, there is no mechanism for providing
security or access control—this is, indeed, a shortcoming of SQL that is solved by
each database system in its own way.
The creation of a table is somewhat more complex, given that you need to declare
its structure as well:
CREATE TABLE (
[],
[...
[]]
);
As you can see, it is necessary to declare a column’s data type—as you probably have
guessed, most database systems are very strict about data typing, unlike PHP. Here’s
the declaration for a simple table that we’ll use throughout the remainder of this
chapter:
CREATE TABLE book (
id INT NOT NULL PRIMARY KEY,
isbn VARCHAR(13),
title VARCHAR(255),
author VARCHAR(255),
publisher VARCHAR(255)
);
Here, we start by declaring a column of type INT that cannot contain NULL values and
is the primary key of our table. The other columns are all VARCHARs of varying length
(note how we are using 255 as the maximum allowable length; this is a “safe bet” and
it is true in many, but not all, database systems).
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)
Creating Indices and Relationships
Indices can be created (as was the example with the primary key above) while you
are creating a table; alternatively, you can create them separately at a later point in
time: