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Restoring Your MySQL Database
Loading Data from a File
One useful feature of MySQL that we have not yet discussed is the LOAD DATA INFILE
statement.This can be used to load table data in from a file. It executes very quickly.
This is a flexible command with many options, but typical usage is something like the
following:
LOAD DATA INFILE "newbooks.txt" INTO TABLE books;
This will read row data from the file newbooks.txt into the table books. By default, data
fields in the file must be separated by tabs and enclosed in single quotes, and each row
must be separated by a newline (\n). Special characters must be escaped out with a slash
(\). All these characteristics are configurable with the various options of the LOAD state-
ment—see the MySQL manual for more details.
To use the LOAD DATA INFILE statement, a user must have the FILE privilege dis-
cussed earlier.
Backing Up Your MySQL Database
In MySQL, there are two ways to do a backup.
The first way is to lock the tables while you copy the physical files, using a LOCK
TABLES command.This has the syntax:
LOCK TABLES table lock_type [, table lock_type ]
Each table should be the name of a table, and the lock type either READ or WRITE.For a
backup, you should only need a READ lock. Users and scripts will still be able to run
read-only queries while you make your backup. If you have a reasonable volume of
queries that alter the database, such as customer orders, this is not a practical solution.
The second, and superior, method is using the mysql_dump command.Typical usage is
something such as
mysqldump opt all-databases > all.sql
This will dump a set of all the SQL required to reconstruct the database to the file called
all.sql.
You should then stop the mysqld process for a moment and restart it with the
log-update[=logfile] option.The updates stored in the log file will give you the

changes made since your dump. (Obviously you should back up the log files in any nor-
mal file backup.)
Restoring Your MySQL Database
If you need to restore your MySQL database, there are, again, a couple of approaches.
If the problem is a corrupted table, you can run myisamchk with the -r (repair) option.
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Chapter 11 Advanced MySQL
If you’ve used the first method for backup, then you can copy the data files back into
the same locations in a new MySQL installation.
If you have used the second method for backup, there are a couple of steps. First, you
need to run the queries in your dump file.This will reconstruct the database up to the
point where you dumped that file. Second, you will need to update the database to the
point stored in the log files. Under UNIX, you can run a command such as
ls -1 -t -r hostname.[0-9]* | xargs cat | mysql
to process the log files in the correct order.
More information about the process of MySQL backup and recovery can be found at
the MySQL Web site:

Further Reading
In these chapters on MySQL, we have focused on the uses and parts of the system most
relevant to Web development, and to linking MySQL with PHP.
If you want to know more, particularly with regard to non-Web applications, or
MySQL administration, you can visit the MySQL Web site at

You might also want to consult Paul Dubois’ book MySQL,available from New Riders
Publishing.
Next
We have now covered the fundamentals of PHP and MySQL. In Chapter 12,“Running
an E-commerce Site,” we will look at the e-commerce and security aspects of setting up

database-backed Web sites.
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III
E-commerce and Security
12 Running an E-commerce Site
13 E-commerce Security Issues
14 Implementing Authentication with PHP and MySQL
15 Implementing Security Transactions with PHP and MySQL
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12
Running an E-commerce Site
THIS CHAPTER INTRODUCES SOME OF THE ISSUES
involved in specifying, designing,
building, and maintaining an e-commerce site effectively.We will examine your plan,
possible risks, and some ways to make a Web site pay its own way.
We will cover
n
What you want to achieve with your e-commerce site
n
Types of commercial Web site
n
Risks and threats
n
Deciding on a strategy
What Do You Want to Achieve?
Before spending too much time worrying about the implementation details of your Web
site, you should have firm goals in mind, and a reasonably detailed plan leading to meet-
ing those goals.
In this book, we make the assumption that you are building a commercial Web site.

Presumably then, making money is one of your goals.
There are many ways to take a commercial approach to the Internet. Perhaps you
want to advertise your offline services or sell a real-world product online. Maybe you
have a product that can be sold and provided online. Perhaps your site is not directly
intended to generate revenue, but instead supports offline activities or acts as a cheaper
alternative to present activities.
Types of Commercial Web Sites
Commercial Web sites generally perform one or more of the following activities:
n
Publish company information through online brochures
n
Take orders for goods or services
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