Administrar BD php

Código Php

table to create :
create table annuaire (
identifiant varchar(10) not null,
nom varchar(100),
prenom varchar(100),
age int(3),
dateajout date,
primary key(identifiant)
);

<?php
// Be careful you msut create the database
$dbhost = "localhost"; 
$user = "kris";
$password = "test";
$usebdd = "example";
//connexion 
$connexion = mysql_connect($dbhost,$user,$password); 
if (!$connexion) {
echo "Impossible to connect";
exit;
}
//sélection of the database
$db = mysql_select_db($usebdd, $connexion);
if (!$db) {
echo "Impossible to find this database";
exit;
}
// insertion od datas
$resultat_sql = mysql_query("insert into annuaire values
('sfim','airey','romuald',23,curdate())", $connexion);
$resultat_sql = mysql_query("insert into annuaire values
('orawat','rawat','olivier',24,curdate())", $connexion);
$resultat_sql = mysql_query("insert into annuaire values
('dmarc','dupuis','marc',32,curdate())", $connexion);
$resultat_sql = mysql_query("insert into annuaire values
('adupont','dupont','antoine',22,curdate())", $connexion);
// sélection od datas
$resultat_sql = mysql_query("select nom,prenom,age from annuaire where age <
30",$connexion);
// number of lines
$nombreligne = mysql_num_rows($resultat_sql);
// Edit the result in a HTML table
echo "<table><tr><th>Nom</th><th>Prenom</th><th>Age</th></tr>";
$i = 0;
while ($i<$nombreligne)
{
$nom = mysql_result($resultat_sql,$i,"nom");
$prenom = mysql_result($resultat_sql,$i,"prenom");
$age = mysql_result($resultat_sql,$i,"age");
echo "<tr><td>$nom</td><td>$prenom</td><td>$age</td></tr>";
$i++;
}
echo "</table>";
?>