Connecting to a MySQL database in Dreamweaver

This TechNote describes a few of the important factors involved in creating a successful MySQL database connection when using the PHP server model in Dreamweaver. It will also cover some basic MySQL user account settings. It's assumed that you have installed and configured MySQL on a local or remote computer.

Errors will occur within Dreamweaver if each point listed below is not completed correctly. A common error that can occur when testing a MySQL connection in Dreamweaver is "An unidentified error has occurred."

	Configure a MySQL user account for the web application itself
	Create a PHP MySQL Site Definition in Dreamweaver
	Setup a MySQL database connection in Dreamweaver

Note: This TechNote is meant to be a basic getting started guide. You should consult the MySQL documentation and other third-party resources to tailor the MySQL account settings to your specific security requirements. To download and install MySQL, visit the MySQL website or consult some of the third-party MySQL websites listed in Dreamweaver websites (TechNote 12607).

MySQL configuration
The default installation of the MySQL database system contains two databases named mysql and test. The mysql database contains six tables that store information about privileges. We will discuss two of these tables: the user table and the db table.

The user table stores information about who can connect to the MySQL server and whether the user has any global level privileges. Because privileges in the user table affect all databases on the MySQL server, usually administrators will have some Ys (yes) in the privilege fields while most standard users have only Ns (no). The db table specifies the databases on the MySQL server that users are allowed to access, and is where most of the standard users' privileges are stored.

Note: There are many graphic interface utilities available to help visually manage MySQL databases, however, this TechNote uses the native MySQL command line client.

Whether you install MySQL on a UNIX, Windows or Mac OS X machine, the command prompt window can be used to administer MySQL. In Windows, the command prompt is opened by selecting Start > Programs > Command Prompt. (On some systems, the Command Prompt may be located under Accessories in the Start > Programs menu.)

Change to the mysql\bin directory by entering the following commands at the command prompt:

During the MySQL installation, MySQL creates an account called root with no password, which can be used to log into the database. It is highly recommended that a password is assigned to this account since root has full control over the MySQL databases. To assign the root account a password run the following command, which will set the root password to new-password. You should replace new-password with a password of your choice that is harder to guess.

It is recommended that separate MySQL accounts are created for each PHP web application. You can create as many MySQL accounts as you wish and assign different rights and permissions to each account. Web application users do not need the same level of privileges as the root account.

To create a separate user account for your web application, connect to MySQL and log in with the superuser account using one of the following methods. In the example below, the account with superuser privileges is the root account. MySQL should prompt you to enter a password when you press the Enter key:

Once logged into MySQL, you will create a user called dbuser (the name is arbitrary) for the web application. Below, are four examples of ways to set up this new user. In all four examples, a new user named dbuser is created. The four privileges granted to this user are SELECT, INSERT, UPDATE and DELETE on any table in the employees database(this database will be referred to as emp in the following examples). The password myPassword will be encrypted in the MySQL database.

	In this example, dbuser can only access the database from localhost. GRANT SELECT, INSERT, UPDATE, DELETE ON emp.* TO dbuser@localhost IDENTIFIED BY "myPassword";
	In this example, dbuser can only access the database from mySite. GRANT SELECT, INSERT, UPDATE, DELETE ON emp.* TO dbuser@mySite IDENTIFIED BY "myPassword";
	In this example, dbuser can only access the database from mySite.myDomain.com. GRANT SELECT, INSERT, UPDATE, DELETE ON emp.* TO dbuser@mySite.myDomain.com IDENTIFIED BY "myPassword";
	In this example, dbuser can access the database from any host. GRANT SELECT, INSERT, UPDATE, DELETE ON emp.* TO dbuser@"%" IDENTIFIED BY "myPassword";

After running the GRANT statement(s), switch from the emp database back into the mysql database by running the following command:

>use mysql

Execute the following SQL statement to observe what changes have been made to the db table in the main mysql database:

SELECT Host, Db, User, Select_priv, Insert_priv, Update_priv, Delete_priv FROM db WHERE User='dbuser';

Here is how the db table will look if all of the GRANT statements listed above are run:

Host	Db	User	Select_priv	Insert_priv	Update_priv	Delete_priv
localhost	emp	dbuser	Y	Y	Y	Y
mySite	emp	dbuser	Y	Y	Y	Y
mySite. myDomain.com	emp	dbuser	Y	Y	Y	Y
%	emp	dbuser	Y	Y	Y	Y

Execute the following SQL statement to observe what changes have been made to the user table in the main mysql database:

SELECT Host, User, Select_priv, Insert_priv, Update_priv, Delete_priv FROM user WHERE User='dbuser';

Here is how the user table will look if all of the GRANT statements above had been run:

Host	User	Select_priv	Insert_priv	Update_priv	Delete_priv
localhost	dbuser	N	N	N	N
mySite	dbuser	N	N	N	N
mySite. myDomain.com	dbuser	N	N	N	N
%	dbuser	N	N	N	N

Note: For security purposes, the dbuser account in the user table should not be modified unless the account needs administrative rights similar to the root or the MySQL administrator account. If these privileges are granted, the dbuser will have access to the system database.

MySQL automatically reads the user and db tables when it starts, and when GRANT and REVOKE statements are issued. If you make any manual changes to the user and db tables, reload the tables to process the changes using this command:

Setting up the PHP / MySQL Site Definition in Dreamweaver
A successful connection to a MySQL database in Dreamweaver depends on correct Site Definition entries when defining the site. Below, is a sample PHP / MySQL Site Definition that uses a Linux PHP server running on a machine identified as mySite.myDomain.com. MySQL is running on another machine identified as mysql1.myDomain.com and Dreamweaver is running on a local workstation. FTP is used to transfer files between the workstation and the Linux web server.

	Local Info:
	Site Name: mySite
	Local Root Folder: C:\mySite\
	Remote Info:
	Access: FTP
	FTP Host: mySite.myDomain.com
	Host Directory: /htdocs/
	Login: webadmin
	Password: *********
	Testing Server:
	Server Model: PHP / MySQL
	Access: FTP
	FTP Host: mySite.myDomain.com
	Host Directory: /htdocs/
	Login: webadmin
	Password: *********
	URL Prefix: http://mySite.myDomain.com/

Create a MySQL database connection in Dreamweaver
Once the MySQL user account has been set up and the site has been defined you can connect to your MySQL database in Dreamweaver. Using the above settings, here are example settings for the MySQL Connection dialog box in Dreamweaver:

Connection Name: choose a name (e.g. connEmp)
MySQL Server: mysql1.myDomain.com
User Name: dbuser
Password: myPassword
Database: enter the name of your database or click on the Select button to choose from a list of MySQL databases running on the server.

Note: For the MySQL Server field you must enter localhost if PHP and MySQL are running on the same machine.

MySQL utilities
There are third-party tools to help configure and manage a MySQL database without having to know SQL. These tools are helpful to those who prefer to work with databases through a visual interface rather than a command line interface. These tools can be downloaded and installed on the machine running the MySQL database or the local workstation. Some popular tools include: PHPMyAdmin, MySQL Control Center (MyCC), EMS MySQL Manager, urSQL, PremiumSoft MySQL Studio, and MySQLGUI.

Additional information
For more details on MySQL, please refer to the MySQL documentation or to the third-party MySQL sites listed in Dreamweaver websites (TechNote 12607).

For more information on unidentified errors, please refer to Unidentified error occurs when testing a PHP / MySQL connection (TechNote 16515).

For general MySQL and PHP troubleshooting tips, please see Testing your PHP application server (TechNote 16383).