Delete MySQL PHP - php

Question

mysql_connect('localhost', 'root', '')
or die(mysql_error());
mysql_select_db('shuttle_service_system')
or die(mysql_error());
$insert="INSERT INTO inactive (ID_No, User_Password, First_Name, Last_Name, Email, Contact_Number)
VALUES('". $ID_No ."','". $UserPassword ."','". $FirstName ."','". $LastName ."','". $Email ."','". $ContactNumber ."')";
$result=mysql_query($insert);
$sql="DELETE FROM users WHERE ID_No = '$ID_No'";
$result2=mysql_query($sql);
if($result && $result2){
echo"Successful!";
} else {
echo "&nbsp Error";
}
Hi guys I have been stuck in delete function of MySQL, I have tried searching the net but when I ran my code it always goes to the else part which means there is an error, the insert is already okay but the delete is not.

Answer 1

PHP variables are allowed in double quotes. Hence try this,
$sql="DELETE FROM users WHERE ID_No = $ID_No";

Answer 2

Your first query was not properly escaped. Rewrite like
$insert="INSERT INTO inactive (`ID_No`, `User_Password`, `First_Name`, `Last_Name`, `Email`, `Contact_Number`)
VALUES('$ID_No','$UserPassword','$FirstName','$LastName','$Email','$ContactNumber')";
This (mysql_*) extension is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should be used. Switching to PreparedStatements is even more better to ward off SQL Injection attacks !

Answer 3

First, use PDO.
Make your connection Database like this:
function connectToDB(){
$host='localhost';
try {
$user = 'username';
$pass = 'password';
$bdd = 'databaseName';
$dns = 'mysql:host='.$host.';dbname='.$bdd.'';
$options = array(
PDO::ATTR_PERSISTENT => true,
PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8",
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
);
return $connexion = new PDO($dns, $user, $pass, $options);
}catch ( Exception $e ) {
echo "Fail to connect: ", $e->getMessage();
die();
}
}
To delete something, here is an example:
function deleteUserWithId($ID_No){
$connexion = connectToDB();
try{
$connexion->exec('DELETE FROM users WHERE ID_No = '.$ID_No);
}catch(Exception $e){
echo "Error: ".$e->getMessage();
}
}
To insert something:
function addInactiveUser($UserPassword,$FirstName ,$LastName ,$Email,$ContactNumber){
$connexion = connectToDB();
$insert = $connexion->prepare('INSERT INTO inactive VALUES(:ID_No,
:User_Password,
:First_Name,
:Last_Name,
:Email,
:Contact_Number
)');
try {
// executing the request
$success = $insert->execute(array(
'ID_No'=>'',
'User_Password'=>$UserPassword,
'First_Name'=>$FirstName ,
'Last_Name'=>$LastName ,
'Email'=>$Email,
'Contact_Number'=>$ContactNumber
));
if($success)
// OK
else
// KO
}
catch (Exception $e){
echo "Error: ".$e->getMessage();
}
}
To make a select:
// If you want to display X user per pages for example
function getAllInactiveUsers($page, $numberInactiveUserPerPage){
$connexion = connectToDB();
$firstInactiveUser = ($page - 1) * $numberInactiveUserPerPage;
$selectAllInactiveUsers = $connexion->prepare('SELECT * FROM inactive ORDER BY ID_No DESC LIMIT '.$firstInactiveUser.','.$numberInactiveUserPerPage);
return $selectAllInactiveUsers ;
}
To get the results of this methods, just do something like this:
$inactiveUsers= getAllInactiveUsers(1,15); // for page 1, display 15 users
$inactiveUsers->execute();
while($row = $inactiveUsers->fetch(PDO::FETCH_OBJ)){
$id = $row->ID_No;
$first_name = $row->First_Name;
// etc...
}
Hope that's help :)

Answer 4

I am not sure if this helps you, but as an alternative you could delete the last entry in the table:
$delQ = mysql_query("SELECT * FROM ph ORDER BY id DESC LIMIT 1" );
while(( $ar = mysql_fetch_array($delQ)) !== false){
mysql_query("DELETE FROM ph WHERE id= $ar[id]");
}