Task2: Variable and Connectivity with MySQL

Variables in PHP

      To storing the values we are using variables, like text strings, numbers and arrays. We can use variable in whole programme. The variables start with $ sign.

Example

$var_name = value;

Rules for variable

• A variable name must start with a letter or an underscore "_"
• A variable name can only contain alpha-numeric characters and underscores (a-z, A-Z, 0-9, and _ )
• A variable name should not contain spaces. If a variable name is more than one word, it should be separated with an underscore ($my_string), or with capitalization ($myString)

MySQL Database

      MySQL is database. MySQL is stored in database objects called tables. A table is a collection of related data entries and it consists of columns and rows.

MySQL Connection

      In PHP, my connection function is:

mysql_connect(servername,username,password);

Example of MySQL connection in PHP

$con = mysql_connect("localhost","peter","abc123");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

// some code
?>

Closing Connection

The connection will be closed automatically when the script ends.

$con = mysql_connect("localhost","peter","abc123");
if (!$con)
  {
  die('Could not connect: ' . mysql_error());
  }

// some code

mysql_close($con);
?>

Reference

n.d (2010). PHP. Retrieved on 23/05/2010 from http://www.w3schools.com/php/default.asp