MySql_* extension is deprecated.

 Learn  MySQLi or PDO_MySQL

1. Why learn?

• MySql_* extension is deprecated as of PHP 5.5.0, and will be removed in the future. 
• MySQLi or PDO_MySQL are better than MySql. You will agree with me, when you learn anyone of these. 
• If you like OO (object-oriented), then you will like these more.
• Full form of MySqLi is MySqLi (improved) .MySql Improved Extension

First I am covering MySqLi then I will cover PDO.

MySqLi has dual interface. Procedural and object-oriented interface. You can choose whatever you like. Exactly same functionality is provided in both interfaces but in different ways. 

 Procedural way example-

<?php

//New way

$mysqli = mysqli_connect($host, $user, $pass, $database); 
$res = mysqli_query($mysqli, "SELECT 'something' FROM table"); 
$row = mysqli_fetch_assoc($res);
echo $row['something'];

//Old way 
$mysql = mysql_connect($host, $user, $pass); 
mysql_select_db($database);
$res = mysql_query("SELECT 'something' FROM table", $mysql); 
$row = mysql_fetch_assoc($res);
echo $row['something']; 
?>




It is very similar to MySql except mysqli_connect in which we have to write database name also. So, we don't need mysql_select_db($database); statement line.

Object oriented way,

$mysqli = new mysqli($host,$user,$pass,$database);
if ($mysqli->connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli->connect_error;
} 
$res = $mysqli->query("SELECT 'something' FROM table"); 
$row = $res->fetch_assoc();
echo $row['something'];

We can even mix both but it's bad way so I am not going to tell that way.

Full list of MySqli function/class can be found at,

http://www.php.net/manual/en/mysqli.summary.php

Prepared Statements

  A prepared statement or a parameterized statement is used to execute the same statement repeatedly with high efficiency. 

This is two step process,

First step,

<?php
$mysqli = new mysqli(......);
/* Prepared statement, stage 1: prepare */ 
if (!($stmt = $mysqli->prepare("INSERT INTO table(column) VALUES (?)"))) {
    //Prepare failed
}//use ?,? for multiple 
?>

Second Step, binding and execution, (? is replaced with real values) 

Example #2 Second stage: bind and execute

<?php 
/* Prepared statement, stage 2: bind and execute */
if (!$stmt->bind_param("column", 'value')) {
    //error happens
}

if (!$stmt->execute()) {
    //execution error.
}?>

Official docs for prepare can be found at, 

http://www.php.net/manual/en/mysqli.quickstart.prepared-statements.php

More coming soon.