Data ain't changed after submitted to mysql - php

Question

i have a code for updating data to myql. It looks doesn't have a problem but it ain't changed
my update code :
//previous data//
....
if (isset($_POST['update'])) {
$nim = mysqli_real_escape_string($connection, ($_POST['nim']));
$name = mysqli_real_escape_string($connection, ($_POST['name']));
$class1 = mysqli_real_escape_string($connection, ($_POST['class2']));
$class2 = mysqli_real_escape_string($connection, ($_POST['class1']));
if (!preg_match("/^[1-9][0-9]*$/",$nim)) {
$error = true;
$nim_error = "NIM only contain numbers";
}
if (!preg_match("/[^a-zA-Z]/",$name)) {
$error = true;
$name_error = "NIM only contain numbers";
}
if (!preg_match("/^[1-9][0-9]*$/",$class1)) {
$error = true;
$class1_error = "Class only contain numbers";
}
if (!preg_match("/^[1-9][0-9]*$/",$class1)) {
$error = true;
$class2_error = "Class only contain numbers";
}
$result = "UPDATE users SET nim='$nim', name='$name', class1='$class1', class1='$class1' WHERE id='$id'";
mysqli_query($connection, $result);
}
?>
and this is my html code :
<div id="popup2" class="overlay">
<div class="popup">
<h2 class="range2">Edit</h2>
<a class="close" href="#">×</a>
<div class="content">
<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<input class="input" type="text" name="nim" placeholder="NIM" required/>
<input class="input" type="text" name="name" placeholder="Name" required/>
<i>SK</i>
<input class="input1" type="text" name="class1" placeholder="00" required/>
<i>-</i>
<input class="input1" type="text" name="class2" placeholder="00" required/>
<input name="update" type="submit" class="button" id="submit" value="Submit">
</form>
</div>
</div>
</div>
is there any wrong code ? Thank you..

Answer 1

It is really hard to explain: Take a look.
If you want to update a single data you will need a identity(Primary
key). That mean which data you want to update.
Below Example: check index.php file
In file index.php change dbname to your database name in connection.
browse project_url/index.php?id=1 [here use any id from your database]
Then update your data.
index.php
//Show existed data againist id
if(isset($_GET['id'])){
$id = $_GET['id'];
$stmt = $pdo->prepare('SELECT * FROM users WHERE id = :id');
$stmt->execute(array('id'=>$id));
$data = $stmt->fetch();
if (empty($data)) {
echo "No data found in user table. Use proper ID.";
}
}
//Update query
$msg = array();
if (isset($_POST['id']) && $_POST['id']!='') { //operation is update, because id exist
if($_POST['nim']!=0 && is_numeric($_POST['nim'])){
$nim = $_POST['nim'];
}else{
$msg[]="Nim only can be number";
}
if($_POST['name']!=''){
$name = $_POST['name'];
}else{
$msg[]="came only can not be empty";
}
if(is_numeric($_POST['class1'])){
$class1 = $_POST['class1'];
}else{
$msg[]="Class1 only can be number";
}
if(is_numeric($_POST['class2'])){
$class2 = $_POST['class2'];
}else{
$msg[]="Class1 only can be number";
}
$id = $_POST['id'];
if(count($msg)==0){
$stmt = $pdo->prepare('UPDATE users SET nim=:nim, name=:name, class1=:class1, class2=:class2 WHERE id=:id');
$result = $stmt->execute(array(
'nim' => $nim,
'name' => $name,
'class1'=> $class1,
'class2'=> $class2,
'id' => $id,
));
if($result){
echo "successfully updated.";
}else{
echo "update failed";
}
}
}else{
//You can run here insert operation because id not exist.
echo "Id not set";
}
?>
<div id="popup2" class="overlay">
<div class="popup">
<h2 class="range2">Edit</h2>
<a class="close" href="#">×</a>
<div class="content">
<?php foreach ($msg as $value) {
echo $value."<br>";
}?>
<form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<?php if(isset($data)){?>
<input class="input" type="hidden" name="id" value="<?php echo $data['id']; ?>" />
<?php } ?>
<input class="input" type="text" name="nim" value="<?php echo isset($data)?$data['nim']:''?>" placeholder="NIM" required/>
<input class="input" type="text" name="name" value="<?php echo isset($data)?$data['name']:''?>" placeholder="Name" required/>
<i>SK</i>
<input class="input1" type="text" name="class1" value="<?php echo isset($data)?$data['class1']:''?>" placeholder="00" required/>
<i>-</i>
<input class="input1" type="text" name="class2" value="<?php echo isset($data)?$data['class2']:''?>" placeholder="00" required/>
<input name="update" type="submit" class="button" id="submit" value="Submit">
</form>
</div>
</div>
</div>

Answer 2

My friend,
only do one thing to resolve this
echo $result = "UPDATE users SET nim='$nim', name='$name', class1='$class1', class1='$class1' WHERE id='$id'";
die;
then submit your form again and you will get your static query into your page then just copy that query and try to run into phpmyadmin then you will get your actual error.