Chapter 6 Server Side

What is PHP?
• PHP was originally an acronym for Personal Home

Pages.
But now it is an acronym for Hypertext Preprocessor.
It was developed as an open source.
It contains a combination of HTML and scripting.
Its file is an extension of .php
How does PHP work?
Cont…
Servers
• PHP is a server-side technology. Therefore, you need to have a server to run

PHP.
What is a PHP File?
• PHP files can contain text, HTML, CSS, JavaScript, and PHP code
• PHP code are executed on the server, and the result is returned to the
browser as plain HTML
• PHP files have extension ".php“
What Can PHP Do?
• PHP can generate dynamic page content.
• PHP can create, open, read, write, delete, and close files on the server.
• PHP can collect form data.
• PHP can send and receive cookies.
• PHP can add, delete, modify data in your database.
• PHP can restrict users to access some pages on your website.
• PHP can encrypt data.
Why We use PHP?
• PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.)

• PHP is compatible with almost all servers used today (Apache, IIS, etc.)
• PHP supports a wide range of databases.
• PHP is free.
• PHP is easy to learn and runs efficiently on the server side.
What Do I Need?
To start using PHP, you can:
• Find a web host with PHP and MySQL support
• Install a web server on your own PC, and then install PHP and MySQL.
Set Up PHP on Your Own PC
However, if your server does not support PHP, you must:
• install a web server
• install PHP
• install a database, such as MySQL
The official PHP website (PHP.net) has installation instructions for PHP.
The PHP script is executed on the server, and the plain HTML result is sent
back to the browser.
Basic PHP Syntax
• A PHP script can be placed anywhere in the document.

<? php
// PHP code goes here
?>
• A PHP script starts with <?php and ends with ?>:
• The default file extension for PHP files is ".php".
• A PHP file normally contains HTML tags, and some PHP scripting code.
Example
<!DOCTYPE html>
<html>
<body>
<h1>My first PHP page</h1>
<?php
echo "Hello World!";
?>
</body>
</html>
Comments in PHP
• A comment in PHP code is a line that is not read/executed as part of the

program. Its only purpose is to be read by someone who is editing the code!
Comments are useful for:
 To let others understand what you are doing .
 To remind yourself what you did .
• PHP supports three ways of commenting:
Example
<!DOCTYPE html>
<html>
<body>
<?php
// This is a single line comment
# This is also a single line comment
/*
This is a multiple lines comment block
that spans over more than
one line
*/
?>
</body>
</html>
PHP Case Sensitivity
• In PHP, all user-defined functions, classes, and keywords (e.g. if, else, while,
echo, etc.) are NOT case-sensitive.
• In the example below, all three echo statements below are legal (and equal):
Example
<!DOCTYPE html>
<html>
<body>
<?php
ECHO "Hello World!<br>";
echo "Hello World!<br>";
EcHo "Hello World!<br>";
?>
</body>
</html>
• However; in PHP, all variables are case-sensitive.
Cont…
• However; in PHP, all variables are case-sensitive.
• Example
• <!DOCTYPE html>
<html>
<body>
<?php
$color="red";
echo "My car is " . $color . "<br>";
echo "My house is " . $COLOR . "<br>";
echo "My boat is " . $coLOR . "<br>";
?>
</body>
</html>
PHP Variables
• Variables are "containers" for storing information:
Cont…
Example
<?php
$x=5;
$y=6;
$z=$x+$y;
echo $z;
?>
Rules for PHP variables:
• A variable starts with the $ sign, followed by the name of the variable
• A variable name must start with a letter or the underscore character
• A variable name cannot start with a number
• A variable name can only contain alpha-numeric characters and
underscores (A-z, 0-9, and _ )
• Variable names are case sensitive ($y and $Y are two different variables)
NOTE: Remember that PHP variable names are case-sensitive!
Declaring PHP Variables
• PHP has no command for declaring a variable.
• A variable is created the moment you first assign a value to it:
Example
<?php
$txt="Hello world!";
$x=5;
$y=10.5;
?>
Note: When you assign a text value to a variable, put quotes around the value.
PHP is a Loosely Type Language
PHP automatically converts the variable to the correct data type, depending
on its value.
PHP Variables Scope
• In PHP, variables can be declared anywhere in the script.
• The scope of a variable is the part of the script where the variable can be
referenced/used.
• PHP has three different variable scopes:
Cont…
• local
• global
• static
Local and Global Scope
• A variable declared outside a function has a GLOBAL SCOPE and can only be accessed outside a
function.
• A variable declared within a function has a LOCAL SCOPE and can only be accessed within that
function.
• The following example tests variables with local and global scope:
• Example
• <?php
$x=5; // global scope

function myTest() {
$y=10; // local scope
echo "<p>Test variables inside the function:</p>";
echo "Variable x is: $x";
echo "<br>";
echo "Variable y is: $y";
}

myTest();

echo "<p>Test variables outside the function:</p>";
echo "Variable x is: $x";
echo "<br>";
echo "Variable y is: $y";
?>
Cont…
• Note: You can have local variables with the same name in different functions,
because local variables are only recognized by the function in which they are
declared.
PHP The global Keyword
• The global keyword is used to access a global variable from within a function.
• To do this, use the global keyword before the variables (inside the function):
Example
<?php
$x=5;
$y=10;
function myTest() {
global $x,$y;
$y=$x+$y;
}
myTest();
echo $y; // outputs 15
?>
PHP The static Keyword
• Normally, when a function is completed/executed, all of its variables are

deleted. However, sometimes we want a local variable NOT to be deleted.
We need it for a further job.
• To do this, use the static keyword when you first declare the variable:
Example
<?php
function myTest() {
static $x=0;
echo $x;
$x++;
}
myTest();
myTest();
myTest();
?>
• Note: The variable is still local to the function.
PHP echo and print Statements
• There are some differences between echo and print:
• echo - can output one or more strings
• print - can only output one string, and returns always 1
NOTE: echo is marginally faster compared to print as echo does not return any
value.
The PHP echo Statement
echo is a language construct, and can be used with or without parentheses:
echo or echo().
Example
<?php
echo "<h2>PHP is fun!</h2>";
echo "Hello world!<br>";
echo "I'm about to learn PHP!<br>";
echo "This", " string", " was", " made", " with multiple parameters.";
?>
Display Variables
• The following example shows how to display strings and variables with the
echo command:
Example
<?php
$txt1="Learn PHP";
$txt2="W3Schools.com";
$cars=array("Volvo","BMW","Toyota");
echo $txt1;
echo "<br>";
echo "Study PHP at $txt2";
echo "My car is a {$cars[0]}";
?>
The PHP print Statement
print is also a language construct, and can be used with or without
parentheses: print or print().
Cont…
Example
<?php
print "<h2>PHP is fun!</h2>";
print "Hello world!<br>";
print "I'm about to learn PHP!";
?>
PHP Data Types
• String, Integer, Floating point numbers, Boolean, Array, Object, NULL.
PHP Strings
• A string is a sequence of characters, like "Hello world!".
• A string can be any text inside quotes. You can use single or double quotes:
Cont…
• Example
• <?php
$x = "Hello world!";
echo $x;
echo "<br>";
$x = 'Hello world!';
echo $x;
?>
PHP Integers
• An integer is a number without decimals.
• Rules for integers:
• An integer must have at least one digit (0-9)
• An integer cannot contain comma or blanks
• An integer must not have a decimal point
• An integer can be either positive or negative
• Integers can be specified in three formats: decimal (10-based), hexadecimal
(16-based - prefixed with 0x) or octal (8-based - prefixed with 0)
Cont…
• The PHP var_dump() function returns the data type and value of variables:
Example
<?php
$x = 5985;
var_dump($x);
echo "<br>";
$x = -345; // negative number
var_dump($x);
echo "<br>";
$x = 0x8C; // hexadecimal number
var_dump($x);
echo "<br>";
$x = 047; // octal number
var_dump($x);
?>
PHP Floating Point Numbers
• A floating point number is a number with a decimal point or a number in

exponential form.
Example
<?php
$x = 10.365;
var_dump($x);
echo "<br>";
$x = 2.4e3;
var_dump($x);
echo "<br>";
$x = 8E-5;
var_dump($x);
?>

PHP Booleans
• Booleans can be either TRUE or FALSE.
• $x=true;
$y=false;
• Booleans are often used in conditional testing.
PHP Arrays
• An array stores multiple values in one single variable.
• In the following example we create an array, and then use the PHP
var_dump() function to return the data type and value of the array:
Example
<?php
var_dump($cars);
?>
PHP Objects
An object is a data type which stores data and information on how to process
that data.
Cont…
• In PHP, an object must be explicitly declared.
• First we must declare a class of object. For this, we use the class keyword.
A class is a structure that can contain properties and methods.
• We then define the data type in the object class, and then we use the data
type in instances of that class:
Example
<?php
class Car
{
var $color;
function Car($color="green") {
$this->color = $color;
}
function what_color() {
return $this->color;
}
}
?>
PHP NULL Value
• The special NULL value represents that a variable has no value. NULL is the
only possible value of data type NULL.
• The NULL value identifies whether a variable is empty or not. Also useful to
differentiate between the empty string and null values of databases.
• Variables can be emptied by setting the value to NULL:
Example
<?php
$x="Hello world!";
$x=null;
var_dump($x);
?>
PHP String Functions
A string is a sequence of characters, like "Hello world!".
The PHP strlen() function
• The strlen() function returns the length of a string, in characters.
Cont…
Example
<?php
echo strlen("Hello world!");
?>
The output of the code above will be: 12
Tip: strlen() is often used in loops or other functions, when it is important to
know when a string ends. (i.e. in a loop, we might want to stop the loop after
the last character in a string).
The PHP strpos() function
• The strpos() function is used to search for a specified character or text
within a string.
• If a match is found, it will return the character position of the first match. If
no match is found, it will return FALSE.
Example
<?php
echo strpos("Hello world!","world");
?>
The output of the code above will be: 6.
PHP Operators
Cont…
Example
<?php
$x=10;
$y=6;
echo ($x + $y); // outputs 16
echo ($x - $y); // outputs 4
echo ($x * $y); // outputs 60
echo ($x / $y); // outputs 1.6666666666667
echo ($x % $y); // outputs 4
?>
PHP Assignment Operators
• The PHP assignment operator is used to write a value to a variable.
• The basic assignment operator in PHP is "=". It means that the left operand
gets set to the value of the assignment expression on the right.
Cont…
Example
Cont…
<?php
$x=10;
echo $x; // outputs 10
$y=20;
$y += 100;
echo $y; // outputs 120
$z=50;
$z -= 25;
echo $z; // outputs 25
$i=5;
$i *= 6;
echo $i; // outputs 30
$j=10;
$j /= 5;
echo $j; // outputs 2
$k=15;
$k %= 4;
echo $k; // outputs 3
?>
Cont…
Cont…
Example
<?php
$a = "Hello";
$b = $a . " world!";
echo $b; // outputs Hello world!
$x="Hello";
$x .= " world!";
echo $x; // outputs Hello world!
?>
Cont…
Example
<?php
$x=10;
echo ++$x; // outputs 11
$y=10;
echo $y++; // outputs 10
$z=5;
echo --$z; // outputs 4
$i=5;
echo $i--; // outputs 5
?>
Cont…
Cont…
Example
<?php
$x=100;
$y="100";
var_dump($x == $y);
echo "<br>";
var_dump($x === $y);
echo "<br>";
var_dump($x != $y);
echo "<br>";
var_dump($x !== $y);
echo "<br>";
$a=50;
$b=90;
var_dump($a > $b);
echo "<br>";
var_dump($a < $b);
?>
Cont..
Cont..
Cont..
Example
<?php
$x = array("a" => "red", "b" => "green");
$y = array("c" => "blue", "d" => "yellow");
$z = $x + $y; // union of $x and $y
var_dump($z);
var_dump($x == $y);
var_dump($x === $y);
var_dump($x != $y);
var_dump($x <> $y);
var_dump($x !== $y);
?>
PHP if...else...else if Statements
Conditional statements are used to perform different actions based on
different conditions.
PHP Conditional Statements
• Very often when you write code, you want to perform different actions for
different decisions. You can use conditional statements in your code to do
this.
• In PHP we have the following conditional statements:
• if statement - executes some code only if a specified condition is true
• if...else statement - executes some code if a condition is true and another
code if the condition is false
• if...elseif....else statement - selects one of several blocks of code to be
executed
• switch statement - selects one of many blocks of code to be executed
PHP - The if Statement
• The if statement is used to execute some code only if a specified condition
is true.
Syntax
if (condition) {
code to be executed if condition is true;
}
• The example below will output "Have a good day!" if the current time (HOUR)
is less than 20:
Cont…
Example
<?php
$t=date("H");
if ($t<"20") {
echo "Have a good day!";
}
?>
PHP switch Statement
• The switch statement is used to perform different actions based on different
conditions.
• Use the switch statement to select one of many blocks of code to be executed.
• Syntax
• switch (n) {
case label1:
code to be executed if n=label1;
break;
case label2:
break;
case label3:
break;
...
default:
code to be executed if n is different from all labels;
}
• Example
• <?php
$favcolor="red";

switch ($favcolor) {
case "red":
echo "Your favorite color is red!";
break;
case "blue":
echo "Your favorite color is blue!";
break;
case "green":
echo "Your favorite color is green!";
break;
default:
echo "Your favorite color is neither red, blue, or green!";
}
?>
PHP while Loops
• PHP while loops execute a block of code while the specified condition is
true.
PHP Loops
• Often when you write code, you want the same block of code to run over and
over again in a row. Instead of adding several almost equal code-lines in a
script, we can use loops to perform a task like this.
• In PHP, we have the following looping statements:
• while - loops through a block of code as long as the specified condition is
true
• do...while - loops through a block of code once, and then repeats the loop as
long as the specified condition is true
• for - loops through a block of code a specified number of times
• For each- loops through a block of code for each element in an array.
Cont..
• The while loop executes a block of code as long as the specified condition is
true.
• Syntax
• while (condition is true ) {
code to be executed ;
}
• The example below first sets a variable $x to 1 ($x=1;). Then, the while loop
will continue to run as long as $x is less than, or equal to 5. $x will increase
by 1 each time the loop runs ($x++;):
Example
<?php
$x=1;
while($x<=5) {
echo "The number is: $x <br>";
$x++;
}
?>
Cont…
• The do...while loop will always execute the block of code once, it will then
check the condition, and repeat the loop while the specified condition is true.
• Syntax
• do {
code to be executed;
} whilecondition
( is true );
• The example below first sets a variable $x to 1 ($x=1;). Then, the do while loop
will write some output, and then increment the variable $x with 1. Then the
condition is checked (is $x less than, or equal to 5?), and the loop will continue
to run as long as $x is less than, or equal to 5:
Example
<?php
$x=1;
do {
$x++;
} while ($x<=5);
?>
Cont…
• Notice that in a do while loop the condition is tested AFTER executing the
statements within the loop. This means that the do while loop would
execute its statements at least once, even if the condition fails the first
time.
PHP for Loops
• PHP for loops execute a block of code a specified number of times.
Syntax
• for (init counter; test counter; increment counter) {
}
Parameters:
• init counter: Initialize the loop counter value
• test counter: Evaluated for each loop iteration. If it evaluates to TRUE, the
loop continues. If it evaluates to FALSE, the loop ends.
• increment counter: Increases the loop counter value
Cont…
Example
<?php
for ($x=0; $x<=10; $x++) {
}
?>
The PHP for each Loop
. The for each loop works only on arrays, and is used to loop through each
key/value pair in an array.
Syntax
For each ($array as $value ) {
}
For every loop iteration, the value of the current array element is assigned to
$value and the array pointer is moved by one, until it reaches the last array
element.
Cont…
Example
<?php
$colors = array("red","green","blue","yellow");
for each ($colors as $value) {
echo "$value <br>";
}
?>
PHP Functions
• User defined functions

Besides the built-in PHP functions, we can create our own functions.
A function is a block of statements that can be used repeatedly in a program.
A function will not execute immediately when a page loads.
A function will be executed by a call to the function.
Create a User Defined Function in PHP
A user defined function declaration starts with the word "function":
Syntax
functionfunctionName () {
code to be executed ;
}
Note: A function name can start with a letter or underscore (not a number).
• Function names are NOT case-sensitive.
Cont…
Example
<?php
function writeMsg() {
echo "Hello world!";
}
writeMsg(); // call the function
?>
PHP Function Arguments
• Information can be passed to functions through arguments. An argument is just like a
variable.
• Arguments are specified after the function name, inside the parentheses. You can add as
many arguments as you want, just seperate them with a comma.
• Example
• <?php
function familyName($fname) {
echo "$fnameRefsnes.<br>";
}
familyName("Jani");
familyName("Hege");
familyName("Stale");
familyName("Kai Jim");
familyName("Borge");
?>
PHP Default Argument Value
• The following example shows how to use a default parameter. If we call the function setHeight()
without arguments it takes the default value as argument:
Example
<?php
function setHeight($minheight=50) {
echo "The height is : $minheight<br>";
}
setHeight(350);
setHeight(); // will use the default value of 50
setHeight(135);
setHeight(80);
?>
PHP Functions - Returning values
To let a function return a value, use the return statement:
Example
<?php
function sum($x,$y) {
$z=$x+$y;
return $z;
}
echo "5 + 10 = " . sum(5,10) . "<br>";
echo "7 + 13 = " . sum(7,13) . "<br>";
echo "2 + 4 = " . sum(2,4);
?>
PHP Arrays
• An array stores multiple values in one single variable:
Example
<?php
echo "I like " . $cars[0] . ", " . $cars[1] . " and " . $cars[2] . ".";
?>
What is an Array?
An array is a special variable, which can hold more than one value at a time.
Create an Array in PHP
• In PHP, the array() function is used to create an array:
array();
• In PHP, there are three types of arrays:
• Indexed arrays - Arrays with numeric index
• Associative arrays - Arrays with named keys
• Multidimensional arrays - Arrays containing one or more arrays
PHP Indexed Arrays
There are two ways to create indexed arrays:
• The index can be assigned automatically (index always starts at 0):
• or the index can be assigned manually:
$cars[0]="Volvo";
$cars[1]="BMW";
$cars[2]="Toyota";
Example
<?php
echo "I like " . $cars[0] . ", " . $cars[1] . " and " . $cars[2] . ".";
?>
Get The Length of an Array - The count() Function
The count() function is used to return the length (the number of elements) of
an array:
Example
<?php
echo count($cars);
?>
Loop Through an Indexed Array
To loop through and print all the values of an indexed array, you could use a for
loop, like this:
Example
<?php
$arrlength=count($cars);

for($x=0;$x<$arrlength;$x++) {
echo $cars[$x];
echo "<br>";
}
?>
PHP Associative Arrays
• Associative arrays are arrays that use named keys that you assign to them.
• There are two ways to create an associative array:
• $age=array("Peter"=>"35","Ben"=>"37","Joe"=>"43");
Cont…
Example
<?php
$age=array("Peter"=>"35","Ben"=>"37","Joe"=>"43");
echo "Peter is " . $age['Peter'] . " years old.";
?>
Loop Through an Associative Array
To loop through and print all the values of an associative array, you
could use a foreach loop, like this:
Example
<?php
$age=array("Peter"=>"35","Ben"=>"37","Joe"=>"43");

foreach($age as $x=>$x_value) {
echo "Key=" . $x . ", Value=" . $x_value;
echo "<br>";
}
?>
PHP Global Variables - Superglobals
PHP $GLOBALS
$GLOBALS is a PHP super global variable which is used to access global
variables from anywhere in the PHP script (also from within functions or
methods).
PHP stores all global variables in an array called $GLOBALS[index ]. The index
holds the name of the variable.
The example below shows how to use the super global variable $GLOBALS:
Example
<?php
$x = 75;
$y = 25;
function addition() {
$GLOBALS['z'] = $GLOBALS['x'] + $GLOBALS['y'];
}
addition();
echo $z;
?>
PHP $_SERVER
$_SERVER is a PHP super global variable which holds information
about headers, paths, and script locations.
The example below shows how to use some of the elements in
$_SERVER:
Example
<?php
echo $_SERVER['PHP_SELF'];
echo "<br>";
echo $_SERVER['SERVER_NAME'];
echo "<br>";
echo $_SERVER['HTTP_HOST'];
echo "<br>";
echo $_SERVER['HTTP_REFERER'];
echo "<br>";
echo $_SERVER['HTTP_USER_AGENT'];
echo "<br>";
echo $_SERVER['SCRIPT_NAME'];
?>
Cont…
Cont…
PHP $_REQUEST
• PHP $_REQUEST is used to collect data after submitting an HTML
form.
Example
<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type="text" name="fname">
<input type="submit">
</form>
<?php
$name = $_REQUEST['fname'];
echo $name;
?>
</body>
</html>
PHP $_POST
• PHP $_POST is widely used to collect form data after submitting an HTML
form with method="post". $_POST is also widely used to pass variables.
Example
<html>
<body>
<form method="post" action="<?php echo $_SERVER['PHP_SELF'];?>">
Name: <input type="text" name="fname">
<input type="submit">
</form>
<?php
$name = $_POST['fname'];
echo $name;
?>
</body>
</html>
PHP $_GET
PHP $_GET can also be used to collect form data after submitting an HTML
form with method="get".
$_GET can also collect data sent in the URL.
Assume we have an HTML page that contains a hyperlink with parameters:
<html>
<body>
<a href="test_get.php?subject=PHP&web=W3schools.com">Test $GET</a>
</body>
</html>
Example
<html>
<body>
<?php
echo "Study " . $_GET['subject'] . " at " . $_GET['web'];
?>
</body>
</html>
PHP Cookies
• A cookie is often used to identify a user.
What is a Cookie?
• A cookie is often used to identify a user. A cookie is a small file that the server embeds on the user's computer.
Each time the same computer requests a page with a browser, it will send the cookie too. With PHP, you can
both create and retrieve cookie values.
Create Cookies With PHP

• A cookie is created with the setcookie() function.
Syntax
• setcookie(name, value, expire, path, domain, secure, httponly);
• Only the name parameter is required. All other parameters are optional.
PHP Create/Retrieve a Cookie
• The following example creates a cookie named "user" with the value "John Doe". The cookie will expire after 30
days (86400 * 30). The "/" means that the cookie is available in entire website (otherwise, select the directory
you prefer).
• We then retrieve the value of the cookie "user" (using the global variable $_COOKIE). We also use the isset()
function to find out if the cookie is set:
Note: The setcookie() function must appear BEFORE the <html> tag.
Cont…
Example
<?php
$cookie_name = "user";
$cookie_value = "John Doe";
setcookie($cookie_name, $cookie_value, time() + (86400 * 30), "/"); // 86400 = 1 day
?>
<html>
<body>
<?php
if(!isset($_COOKIE[$cookie_name])) {
echo "Cookie named '" . $cookie_name . "' is not set!";
} else {
echo "Cookie '" . $cookie_name . "' is set!<br>";
echo "Value is: " . $_COOKIE[$cookie_name];
}
?>
</body>
</html>
PHP Sessions
• A session is a way to store information (in variables) to be used across multiple pages.
• Unlike a cookie, the information is not stored on the users computer.
• Session variables hold information about one single user, and are available to all pages in one application.
• If you need a permanent storage, you may want to store the data in a database.
• A session is started with the session_start() function.
• Session variables are set with the PHP global variable: $_SESSION.
Example
<?php
// Start the session
session_start();
?>
<!DOCTYPE html>
<html>
<body>

<?php
// Set session variables
$_SESSION["favcolor"] = "green";
$_SESSION["favanimal"] = "cat";
echo "Session variables are set.";
?>
</body>
</html>
Cont…
• Note: The session_start() function must be the very first thing in your document. Before any HTML tags.
Get PHP Session Variable Values
• Example
<?php
session_start();
?>
<!DOCTYPE html>
<html>
<body>
<?php
// Echo session variables that were set on previous page
echo "Favorite color is " . $_SESSION["favcolor"] . ".<br>";
echo "Favorite animal is " . $_SESSION["favanimal"] . ".";
?>
</body>
</html>
Destroy a PHP Session
• To remove all global session variables and destroy the session, use session_unset() and session_destroy():
Cont…
Example
<?php
session_start();
?>
<!DOCTYPE html>
<html>
<body>
<?php
// remove all session variables
session_unset();
// destroy the session
session_destroy();
?>
</body>
</html>
PHP MySQL Database
• With PHP, you can connect to and manipulate databases.
• MySQL is the most popular database system used with PHP.
What is MySQL?
• MySQL is a database system used on the web
• MySQL is a database system that runs on a server
• MySQL is ideal for both small and large applications
• MySQL is very fast, reliable, and easy to use
• MySQL uses standard SQL
• MySQL compiles on a number of platforms
• MySQL is free to download and use
• MySQL is developed, distributed, and supported by Oracle Corporation
The data in a MySQL database are stored in tables. A table is a collection of related data, and it consists of
columns and rows.
Database Queries
• A query is a question or a request.
• We can query a database for specific information and have a record set returned.
Example:
SELECT LastName FROM Employees

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What is PHP?

• PHP was originally an acronym for Personal Home

• PHP is a server-side technology. Therefore, you need to have a server to run

• PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.)

• A PHP script can be placed anywhere in the document.

• A comment in PHP code is a line that is not read/executed as part of the

• Normally, when a function is completed/executed, all of its variables are

• A ﬂoating point number is a number with a decimal point or a number in

• User deﬁned functions

Create Cookies With PHP

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