To update a data that already exist in the database, UPDATE statement is used.
In the below example we update the employee data from MySQL database.
we used 2 file for update data
<?php
$servername='localhost';
$username='root';
$password='';
$dbname = "crud";
$con=mysqli_connect($servername,$username,$password,"$dbname");
if(!$conn){
die('Could not Connect My Sql:' .mysql_error());
}
?>
<?php
include_once 'database.php';
$result = mysqli_query($conn,"SELECT * FROM employee");
?>
<!DOCTYPE html>
<html>
<head>
<title> Retrive data</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<?php
if (mysqli_num_rows($result) > 0) {
?>
<table>
<tr>
<td>Sl No</td>
<td>First Name</td>
<td>Last Name</td>
<td>City</td>
<td>Email id</td>
<td>Action</td>
</tr>
<?php
$i=0;
while($row = mysqli_fetch_array($result)) {
?>
<tr>
<td><?php echo $row["id"]; ?></td>
<td><?php echo $row["first_name"]; ?></td>
<td><?php echo $row["last_name"]; ?></td>
<td><?php echo $row["city_name"]; ?></td>
<td><?php echo $row["email"]; ?></td>
<td><a href="update-process.php?id=<?php echo $row["id"]; ?>">Update</a></td>
</tr>
<?php
$i++;
}
?>
</table>
<?php
}
else
{
echo "No result found";
}
?>
</body>
</html>
<?php
include_once 'database.php';
if(count($_POST)>0) {
mysqli_query($conn,"UPDATE employee set userid='" . $_POST['userid'] . "', first_name='" . $_POST['first_name'] . "', last_name='" . $_POST['last_name'] . "', city_name='" . $_POST['city_name'] . "' ,email='" . $_POST['email'] . "' WHERE userid='" . $_POST['userid'] . "'");
$message = "Record Modified Successfully";
}
$result = mysqli_query($conn,"SELECT * FROM employee WHERE userid='" . $_GET['userid'] . "'");
$row= mysqli_fetch_array($result);
?>
<html>
<head>
<title>Update Employee Data</title>
</head>
<body>
<form name="frmUser" method="post" action="">
<div><?php if(isset($message)) { echo $message; } ?>
</div>
<div style="padding-bottom:5px;">
<a href="retrieve.php">Employee List</a>
</div>
Username: <br>
<input type="hidden" name="userid" class="txtField" value="<?php echo $row['userid']; ?>">
<input type="text" name="userid" value="<?php echo $row['userid']; ?>">
<br>
First Name: <br>
<input type="text" name="first_name" class="txtField" value="<?php echo $row['first_name']; ?>">
<br>
Last Name :<br>
<input type="text" name="last_name" class="txtField" value="<?php echo $row['last_name']; ?>">
<br>
City:<br>
<input type="text" name="city_name" class="txtField" value="<?php echo $row['city_name']; ?>">
<br>
Email:<br>
<input type="text" name="email" class="txtField" value="<?php echo $row['email']; ?>">
<br>
<input type="submit" name="submit" value="Submit" class="buttom">
</form>
</body>
</html>