<?php
$con=mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$city="Sandnes";

// Create a prepared statement
$stmt=mysqli_stmt_init($con);

if (mysqli_stmt_prepare($stmt,"SELECT District FROM City WHERE Name=?"))
{

// Bind parameters
mysqli_stmt_bind_param($stmt,"s",$city);

// Execute query
mysqli_stmt_execute($stmt);

// Bind result variables
mysqli_stmt_bind_result($stmt,$district);

// Fetch value
mysqli_stmt_fetch($stmt);

printf("%s is in district %s",$city,$district);

// Close statement
mysqli_stmt_close($stmt);
}

mysqli_close($con);
?>