creating a simple database this shows you how to set up a database using phpmyadmin (installed with...

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.

• 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

PHP scripting language

MySQL database

Apache web server

Windows 7 operating system

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 databasescreen should appear

• The first time you use it,the default username is root, with no password

• Enter the username rootand 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):

phpMyAdminSome 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:

• The next step can be done in Dreamweaver

Accessing the database using PHP

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):

mysqli_connect(“locahost”,”root”,””,”simpledata”);

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?