This document provides an overview of PHP and MySQL. It discusses key PHP elements like variables, arrays, conditional statements, and loops. It also covers PHP statements, naming variables, outputting values, performing calculations, working with arrays, conditional logic, and loops. The document then discusses connecting to and querying MySQL databases, and how to insert, update, delete data. It also covers building forms, getting form input, and basic file input/output in PHP.

1. Php & mySQL

2. Operational Trail

3. Why PHP
 Open Source
 Very good support
 C/Java like language
 Cross Platform (Windows, Linux, Unix)
 Powerful, robust and scalable

4. PHP Elements
 Variables: placeholders for unknown or changing
values
 Arrays: a variable to hold multiple values
 Conditional Statements: decision making
 Loops: perform repetitive task
 Functions: perform preset task or sub task

5. PHP statements
<?php
your statement is here;
don„t forget to end each statement with semicolon
(“;”);
anything within this scope must be recognized by
php or you‟ll get error;
?>

6. Naming variables
 Start with dollar sign ($)
 First character after $ cannot be number
 No spaces or punctuation
 Variable names are case-sensitive
 You‟re free to choose your own but …
 … meaningful naming is much better.

7. Assigning values to variables
 $myVar = $value;
 $myVar = 3.4; # assign a number
 $myVar = “I‟m cute”; // Assign a string
 $myVar = $yourVar; /* assign a variable */
 $myVar = “$name is a terrible creature”;

8. PHP Output & comments
 echo:
 echo “you‟re a creature”; // print you‟re a creature
 echo $name; /* print value of variable $name */
 echo(“my creatures”); # print my creatures
 print:
 print “you‟re a creature”;
 print $name;
 print(“my creatures”);
 Also printf and sprintf

9. Joining together
 Joining string
 $var = “Digital”.”Multimeter”;
 Joining variables
 $var = $var1.$var2.$var3……. ;
 $var = “$var1 $var2 $var3 …… “;
 Joining string and variable
 $var = $var1.”Zener diode”;
 $var .= “blogger”;

10. Calculation
Operation Operator Example
Addition + $x + $y
Subtraction - $x - $y
Multiplication * $x * $y
Division / $x / $y
Modulo Division % $x % $y
Increment ++ ++$x @ $x++
Decrement -- --$x @ $x--

11. Array
 Declaration
 $RGBcolor = array(“red”, “Blue”, “Green);
 $mycar[] = “Rapide”;
 Access
 $myarray[element number]
 Functions
 array_pop(); array_push(); array_rand();
array_reverse; count(array); sort(array);
print_r(array)

12. Making decision (if, if else, elseif)
if(condition is true) {
//code will be executed here
}
if(condition is true) {
//code will be executed here
}
else {
//code will be executed if condition is false
}
if(condition 1) { }
elseif (condition 2) { }
else { }

13. Comparison operator
Symbol Name
== Equality
!= Inequality
<> Inequality
=== Identical
!== Not identical
> Greater than
>= Greater/equal than
< Less than
<= Less or equal than

14. Logical Operators
Symbol Name Use
&& Logical AND True if both operands are true
and Logical AND Same as &&
|| Logical OR True if not both operands are
false
or Logical OR Same as ||
xor Exclusive OR True if one of operands is true
! NOT Test for false

15. Switch statement
switch(variable being tested) {
case value1:
statement;
break;
case value2:
statement;
break;
.
.
.
.
default:
statment
}

16. Conditional (ternary) operator
 condition ? value if true : value if false;
$age = 17;
$fareType = $age > 16 ? 'adult' : 'child';

17. Loop
 while(condition is true) { statement; }
 do { statement; } while (condition is true);
 for(initial value; test; increase/decrease)
{statement;}
 foreach(array_name as temporary variable) {
statement;}

18. Breaking loop
 break: exit loop;
 continue: exit current loop but continue next
counter

19. PHP Function
 A block of code that performs specific task
represented by a name and can be called
repeatedly.
function function_name()
{
//code is here
return var; // may return value
}

20. Date & Time
 time(): timestamp from 1st January 1970
 date(format, timestamp):
 Format:-
 d: day of the month (1-31)
 m: month (1-12)
 Y: year in 4 digits
 Timestamp (optional)
 Default is current date and time
 Date Add / Date Diff
 Under DateTime class: DateTime:add, DateTime:diff

21. String function
 strlen(str): string length
 strpos(str, str_find, start): find string occurance
 strrev(str): string reverse
 substr(str, start_str, length): return part of string
 substr_replace(str, replacement, start, length):
replace part of string

22. Math Function
 Absolute value: abs(0 – 300)
 Exponential: pow(2, 8)
 Square root: sqrt(100)
 Modulo: fmod(20, 7)
 Random: rand()
 Random mix & max: rand(1, 10)
 Trigonometry: sin(), cos(), tan()

23. Building Form & input
 <form action=“” method=“URL” enctype=“data">
</form>
 method: get or post
 action: URL to be accessed when form is submitted
 enctype: type of data to be submit to the server
 All inputs must be within the form
 Textfield = <input type=“text” name=“”>
 Checkbox = <input type=“checkbox” name=“”>
 Radio Button = <input type=“radio” name=“”>
 Textarea = <textarea name=“”></textarea>
 List = <select name=“”><option
value=“”></option></select>

24. Getting information from form
 print_r($_POST): form data retrieval in array
 $_POST: contains value sent through post
method
 $_GET: contains value sent through get method

25. MySQL function (connection)
 Connection to database
 mysql_connect(servername, username,
password)
<?php
$test = mysql_connect(“localhost”, “admin”, “pass”);
if($test)
echo “success”;
else
die(“cannot connect maa…”);
?>
 Close connection using
mysql_close(connection_name)

26. MySQL (query)
 Select database: mysql_select_db(“database”,
connection);
 Run query: mysql_query(“SQL query);
<?php
$test = mysql_connect(“localhost”, “root”,””);
mysql_select_db(“data”, $test);
mysql_query(“Select * from table”);
?>
 SQL query: SELECT fieldname FROM tablename

27. MySQL (Display query)
 mysql_fetch_array($result)
 $result is array of data
 Example:
<?php
$result = mysql_query(“MySQL select
query”);
while($row = mysql_fetch_array($result)) {
echo $row[„fieldname‟];
}
?>

28. MySQL insert data
 SQL command: INSERT INTO table_name
(field1, field2, …) VALUES (value1, value2, …)
 Example:
mysql_query("INSERT INTO Address (No, Road,
Postcode) VALUES (11, „Jalan 19/2C', 40000)");

29. MySQL update data
 SQL command: UPDATE table_name SET
field1=value1, field2=value2,... WHERE
field=some_value
 Example:
mysql_query(“UPDATE Address SET
Postcode=40900 WHERE No=13");

30. MySQL delete data
 SQL command: DELETE FROM table_name
WHERE some_column = some_value
 Example:
mysql_query(“DELETE from Address WHERE
Postcode=40900");

31. File input/output