Using the PHP Sql UPDATE command we can modify the data in the MySQL table.
syntax:
UPDATE table_name SET field_name = new_value WHERE [Clause]

Example:


<?php
$dbhost = "localhost";
$dbuser = "your_username";
$dbpass = "your_password";
$dbname = "basename";
$conn = mysqli_connect($dbhost, $dbuser, $dbpass , $dbname);
// Check connection
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$sql = "UPDATE members SET name ='John' WHERE id='1'";
if (mysqli_query($conn, $sql)) {
echo "The field has been updated sucessfuly.";
} else {
echo "The field has NOT been updated." . mysqli_error($conn);
}
mysqli_close($conn);
 ?>

Example how update multiple fields

syntax:
UPDATE table_name SET field_name1 = new_value, field_name2 = new_value, field_name3 = new_value, WHERE [Clause]


<?php
$dbhost = "localhost";
$dbuser = "your_username";
$dbpass = "your_password";
$dbname = "basename";
$conn = mysqli_connect($dbhost, $dbuser, $dbpass , $dbname);
// Check connection
if (!$conn) {
die("Connection failed: " . mysqli_connect_error());
}
$sql = "UPDATE members SET name ='John', lastname='Parker', email='johnparker@gmail' WHERE id='1'";
if (mysqli_query($conn, $sql)) {
echo "The fields has been updated sucessfuly.";
} else {
echo "The fields has NOT been updated." . mysqli_error($conn);
}
mysqli_close($conn);
 ?>