使用新条目覆盖MYSQL数据库中的条目

Question

I am trying to replace previous entries in MYSQL database each time new data is available, I have the following PHP code but it seems to add new entries each time. Please help, thanks.

I have tried using REPLACE but it still does not work, could anyone tell me what it is I am doing wrong?

<?php

header('Content-Type: application/json');

$data = json_decode(file_get_contents('php://input'), true);

$mysqli = new mysqli("localhost","dbuser","Pa55uu0Rd","iewdb");

if (mysqli_connect_errno())
{
    echo json_encode(array('error' => 'Failed to connect to MySQL: ' . mysqli_connect_error() ));
    return;
}

if(!$data)
{
    echo json_encode(array('error' => 'Error input data'));
    return;
}
    $usernme = $data['usernme'];
    $longitude = $data['longitude'];
    $latitude = $data['latitude'];

$user = $mysqli->query("SELECT id FROM Users WHERE usernme = '$usernme' LIMIT 1");  

$user_id = $user->fetch_object();

if(!$user_id)
{     
     $mysqli->query("INSERT INTO Users (usernme) VALUES ('$usernme');");

     $user_id->id = $mysqli->insert_id;
}

if($longitude && $latitude)
{
    $mysqli->query("REPLACE INTO Locations (User_id,Longitude, Latitude) VALUES ($user_id->id,$longitude,$latitude);");
} 

$mysqli->close();

echo json_encode(array('user_id' => $user_id->id));

Answer 1

use update query something like this

UPDATE MyTable
SET User_id = 'USER_ID_VALUE', Longitude='LONGITUDE_VALUE', Latitude='LATITUDE_VALUE' 
WHERE SomeOtherColumn LIKE '%PATTERN%'