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Creating a simple database This shows you how to set up a database using PHPMyAdmin (installed with WAMP) Stack System • In order to develop a web page which runs off a back end data base you will need to have a stack system in place, e.g. PHP MySQL Apache Windows 7 scripting language database web server operating system • It is possible to create a stack on a standalone PC or server by installing WAMP Server (freely available as a download); WAMP works on top of Windows. WAMP has Apache web server, MySQL database, and PHP Download WAMP • Download WAMP server (www.wampserver.com/en/)and install. By default it places a folder www inside the wamp folder on the C: drive Make sure WAMP is running • There should be a green W icon in the notification tray in the lower right of the screen. A green icon means the WAMP server is running. • If it is red it is turned off. • If it is orange, there may be a problem (e.g. another server already running, an application using the port). • You can also run WAMP server by choosing Programs > WampServer > Start WampServer phpMyAdmin • Open a web browser and type localhost (the default name for a home web server URL address). You should come up with a screen: phpMyAdmin • Click phpmyadmin • The phpmyadmin database screen should appear • The first time you use it, the default username is root, with no password • Enter the username root and click Go phpMyAdmin • The MySQL database should open. • Click the databases tab • Enter simpledata for the name of the new database and click Create phpMyAdmin • Decide on the database structure: it is usually best to sketch this. • Data is contained in a table called feedback • Use the sketch below (an example): • The example table has 3 columns, each column representing a field name • The rows are the records representing the data (examples shown) phpMyAdmin • A list of databases appears with simpledata in the list • Create a table by clicking the name of the database (simpledata) phpMyAdmin • Type a name for the table: feedback • Enter 3 as the number of columns (fields) • Click Go (on the far right of the window) phpMyAdmin • The table structure should appear like below: • The 3 columns are now represented by the 3 rows now phpMyAdmin • Enter the names for the first column. This represents the fields • Enter the Type and Length/Values, then click Save (lower right): phpMyAdmin Some common types include: • INT = Integer (a number without a decimal point) • CHAR = Characters (can hold text up to a specific length) • VARCHAR = Variable Length Characters (a text field that is not a fixed width). • TEXT = For holding large amounts of text. • DATE = Can only hold dates. • DATETIME = Can hold both a date and a time. phpMyAdmin • You should see the name feedback as the name of the table, and simpledata as the name of the database • To add data click Insert along the row of tabs phpMyAdmin • Add some values, e.g. • Click Go phpMyAdmin • Set one of the rows as a primary key. Click Primary on the row name • This sets the name as the primary key. The primary key of a table uniquely identifies each record in the table. Every database table should have one or more columns designated as the primary key. • When click, the primary key looks greyed out phpMyAdmin • Click Browse to view the data in the table: Accessing the database using PHP • The next step can be done in Dreamweaver Accessing the database using PHP • Before we can access data in a database, we must open a connection to the MySQL server. • In PHP, this is done with the mysqli_connect() function. Syntax: mysqli_connect(host,username,password,dbname); The details you are using (from our initial plan): simpledata mysqli_connect(“locahost”,”root”,””,”simpledata”); Accessing the database using PHP • Create a new PHP file, e.g. in Dreamweaver. • Enter some PHP script. The following opens the connection to the server and database simpledata.php <?php // Create connection $con=mysqli_connect("localhost","root","","simpledata"); // Check connection if (mysqli_connect_errno()) { echo "Failed to connect to MySQL: " . mysqli_connect_error(); } ?> • An If statement checks for any errors and displays an error message if the connection fails. • No error messages mean it works! Accessing the database using PHP • PHP script created in Dreamweaver. Presenting a database using PHP • • The SELECT statement is used to select data from a database: Add the following PHP <?php $result = mysqli_query($con,"SELECT * FROM feedback"); while($row = mysqli_fetch_array($result)) { echo $row['name'] . " " . $row['rating']; echo "<br>"; } mysqli_close($con); ?> • The data from the table feedback is returned by the mysqli_query() function and stored in the $result variable. • The mysqli_fetch_array() function returns the first row from the table as an array variable &row. • The while loop allows mysqli_fetch_array() to return the next row in the recordset. The while loop loops through all the rows. • To echo the value of each row, we use the PHP $row array variable ($row['FirstName'] and $row['LastName']). Presenting a database using PHP • The source code and live view will look similar to this Preview web page in browser • You have used MySQL (Structured Query Language) with PHP to access a database. • If you open the page in a browser and view source (right click the web page) you should see something like this: • Notice your code entered in Dreamweaver is not shown to the end user • This helps with security, as the database details are not shown Add HTML tags (elements) • When viewing source the HTML is very basic. • Try adding HTML elements (tags), e.g. <HTML>, <BODY>, <TITLE>, <HEAD>, etc. • \n is an escape character and allows line breaks in the code Edit Database • Add new records to the database in PHPmyAdmin • Test the output in Dreamweaver Edit Database • Click Browse to see added rows: Back to Dreamweaver • Refresh the page in Dreamweaver Editing MySQL • You can change the PHP and edit the MySQL code to be more selective in the process. • For more info on MySQL, check http://www.w3schools.com/php/php_mysql_intro.asp E.g. to select from database only records where the name is “Sam Lowry” change the line $result = mysqli_query($con,"SELECT * FROM feedback"); To $result = mysqli_query($con,"SELECT * FROM feedback WHERE name=‘Sam Lowry'"); Editing MySQL MySQL • This is the basics of using MySQL. • Many websites use MySQL, including Google search engine. • MySQL is freely downloadable, light and powerful, and simple to use once you know it more. • Like PHP there are a lot of help forums and web pages providing support and guidance. • Many Content Management Systems (CMS), e.g. WordPress, use PHP with MySQL • Try finding out more about MySQL. Where else is it used?