update query not working php - php

Question

I'm working on a project and I'm suppose to update the another user's details using the $_GET method. My problem is that when user clicks on the id, it does go to edit page but when i change something and press the update button, it does not update. I'm not sure what am i doing wrong here.. I would really appreciate f someone can help me.
//Edit
My code is working now guys, I just changed the $_POST to $_REQUEST now and my form is updated.. Thank you all for helping me.. Thank you.. Here is my edited code.. I've taken out the oassword field, but i have a doubt.. Is using request safe?
<?php
include '../../connection.php';
$sid = $_REQUEST['sid'];
$query = "SELECT * FROM STUDENT WHERE STU_ID='$sid'";
$result = mysqli_query($connection, $query);
if(mysqli_num_rows($result)>0){
while($row = mysqli_fetch_assoc($result)){
$unm = $row["STU_UNAME"];
$fnm = $row["STU_FNAME"];
$lnm = $row["STU_LNAME"];
$dob = $row["STU_DOB"];
$add = $row["STU_ADD"];
$tlp = $row["STU_PHONE"];
$sem = $row["STU_SEM"];
$img = $row["STU_IMG"];
$sts = $row["STU_STATUS"];
$cid = $row["CRS_ID"];
}
}
else{
$no = "0 result!";
}
if($_SERVER["REQUEST_METHOD"] == "POST"){
//insert details in data
$sid = $_POST["sid"]; $snm = $_POST["snm"]; $fst = $_POST["fnm"]; $lst = $_POST["lnm"]; $sdb = $_POST["dob"];
$sad = $_POST["add"]; $shp = $_POST["tlp"]; $stt = $_POST["sts"]; $sem = $_POST["sem"]; $cid = $_POST["cid"];
$sql = "UPDATE STUDENT SET
STU_ID='$sid', STU_UNAME='$snm', STU_FNAME= '$fst', STU_LNAME='$lst', STU_DOB='$sdb', STU_ADD='$sad', STU_PHONE='$shp',
STU_STATUS='$stt', STU_SEM='$sem', CRS_ID = '$cid' WHERE STU_ID='$sid'";
//check if data is updated
if (mysqli_query($connection, $sql)) {
header("Location: searchStudent.php");
}
else {
echo "Error: " . $sql . "<br>" . mysqli_error($connection);
}
}
?>
Here's my form code:
<form class="contact_form" method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
<ul>
<li>
<h2>Edit Students Details</h2>
<span class="required_notification">* Denotes Required Field</span>
</li>
<li>
<label for="id">Student ID: </label>
<input type="text" name="sid" value="<?php echo $sid;?>"/>
</li>
<li>
<label for="name">Username: </label>
<input type="text" name="snm" value="<?php echo $unm;?>"/>
</li>
<li>
<label for="name">First Name: </label>
<input type="text" name="fnm" value="<?php echo $fnm;?>"/>
</li>
<li>
<label for="name">Last Name: </label>
<input type="text" name="lnm" value="<?php echo $lnm;?>"/>
</li>
<li>
<label for="dob">Date of Birth: </label>
<input type="date" name="dob" value="<?php echo $dob;?>"/>
</li>
<li>
<label for="add">Address: </label>
<textarea name="add" rows="4" cols="50"><?php echo $add;?></textarea>
</li>
<li>
<label for="tlp">Phone: </label>
<input type="text" name="tlp" value="<?php echo $tlp;?>"/>
</li>
<li>
<label for="sts">Status: </label>
<select name="sts">
<option selected><?php echo $sts;?></option>
<option value="FULLTIME">FULL TIME</option>
<option value="PARTTIME">PART TIME</option>
</select>
</li>
<li>
<label for="sem">Semester: </label>
<select name="sem">
<option selected><?php echo $sem;?></option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
<option value="7">7</option>
</select>
</li>
<li>
<label for="crs">Course: </label>
<select name="cid">
<option selected><?php echo $cid;?></option>
<option value="AL">AL</option>
<option value="DBM">DBM</option>
<option value="DIT">DIT</option>
<option value="DTM">DTM</option>
<option value="FIS">FIS</option>
</select>
</li>
<li>
<button class="submit" type="submit" name="update">Update</button>
</li>

Answer 1

Make sure your form method is POST
Try this code:
<?php
include '../../connection.php';
//
$id = $_POST['id'];
$query = "SELECT * FROM STUDENT WHERE STU_ID='$id'";
$result = mysqli_query($connection, $query);
if(mysqli_num_rows($result)>0){
while($row = mysqli_fetch_assoc($result)){
$unm = $row["STU_UNAME"];
$fnm = $row["STU_FNAME"];
$lnm = $row["STU_LNAME"];
$pwd = $row["STU_PWD"];
$dob = $row["STU_DOB"];
$add = $row["STU_ADD"];
$tlp = $row["STU_PHONE"];
$sem = $row["STU_SEM"];
$img = $row["STU_IMG"];
$sts = $row["STU_STATUS"];
$cid = $row["CRS_ID"];
}
}
else{
$no = "0 result!";
}
$pwdErr = $cpwdErr= "";
if($_SERVER["REQUEST_METHOD"] == "POST"){
if($_POST["pwd"] == $_POST["cpwd"]){
if(strlen($_POST["pwd"])>8){
//insert details in data
$sid = $_POST["sid"]; $pwd = $_POST["pwd"]; $snm = $_POST["snm"]; $fst = $_POST["fnm"]; $lst = $_POST["lnm"];
$sdb = $_POST["dob"]; $sad = $_POST["add"]; $shp = $_POST["tlp"]; $stt = $_POST["sts"]; $sem = $_POST["sem"];
$cid = $_POST["cid"];
$sql = "UPDATE STUDENT SET
STU_ID='$sid', STU_PWD='$pwd', STU_UNAME='$snm', STU_FNAME= '$fst', STU_LNAME='$lst', STU_DOB='$sdb', STU_ADD='$sad', STU_PHONE='$shp',
STU_STATUS='$stt', STU_SEM='$sem', CRS_ID = '$cid' WHERE STU_ID='$id'";
//check if data is updated
if (mysqli_query($connection, $sql)) {
header("Location: searchStudent.php");
}
else {
echo "Error: " . $sql . "<br>" . mysqli_error($connection);
}
}
else{
$pwdErr = "Invalid/Password must be more than 8 characters!";
}
}
else{
$cpwdErr = "Password not same!";
}
}
?>
Get ride for how to use prepare statement with example here.
Hope this help you well!

Answer 2

Your error is your are using POST in your form but getting its value with get change $_get with $_POST
$id = $_POST['id'];

Answer 3

well problem is that id you are posting is "sid" but you are using just "id" like $_POST['id'] instead of $_POST['sid']. so use this -
$id = $_POST['sid'];
instead of -
$id = $_POST['id']