PHP update mysqli only works until closing browser - php

Question

I have a question about the update function in mysqli.
For school, I'm trying to create a click counter for my website which counts how many times a user has visited a certain page.
So far I've come up with this:
<?php
/*
* ToDo: Check why number of clicks goes back to two when completely
* refreshing page.
*
*/
include("init.php");
session_start();
//Count variable
$clicks = 0;
//Query for checking if there are any entry's in the database
$query = "SELECT * FROM `beoordelingen`.`clickcounter` WHERE `game_id`={$id}";
$result = $conn->query($query);
//If query returns false
if (!mysqli_num_rows($result)) {
//Create entry in database
$insert = "INSERT INTO `beoordelingen`.`clickcounter` (`ID`, `game_id`, `clicks`) VALUES (NULL, '1', '1');";
$createEntry = $conn->query($insert);
}
//If query returns true
else {
//Setting the number of clicks equal to $clicks
while ($data = $result->fetch_assoc()) {
$clicks = $data['clicks'];
}
//Insert new number into database
$sql="insert into `clickcounter` set `clicks`='{$clicks}', `game_id`='{$id}'
on duplicate key update
`clicks`=`clicks`+1;";
$insertInto = $conn->query($sql);
//Echo current number of clicks
echo $clicks;
}
?>
The actual problem is that my update statement doesn't seem to work properly. If anyone would be able to spot why it doesn't work I'd be very happy.
The database is as following;
Beoordelingen <- Database
clickcounter <- Table which has the following three columns:
1. ID
2. game_id
3. clicks
The scripts does add an entry into the databse with click count 2. So when I reload the page it says 2. And when refreshing it counts up, but doesn't update the table.
Thanks! If anything is unclear please ask me!

Answer 1

Theoretically you should be able to do all of it in one query if game_id is unique.
Given the following table structure the sql query below will insert if the relevant record does not exists and then update if it does.
create table `clickcounter` (
`id` int(10) unsigned not null auto_increment,
`game_id` int(10) unsigned not null default '0',
`clicks` int(10) unsigned not null default '0',
primary key (`id`),
unique index `game_id` (`game_id`)
)
engine=innodb;
The trick is setting the indices on your table correctly ~ initially you don't know the value of the ID and I would guess that is an auto increment primary key? So, set a unique key on game_id...I hope it helps!
/* Could even change `clicks`='{$clicks}' to `clicks`=1 in initial insert */
$sql="insert into `clickcounter` set `clicks`='{$clicks}', `game_id`='{$id}'
on duplicate key update
`clicks`=`clicks`+1;";
<?php
include("init.php");
session_start();
/* Where / how is "$id" defined? */
/* insert new record / update existing */
$sql="insert into `clickcounter` set `clicks`=1, `game_id`='{$id}'
on duplicate key update
`clicks`=`clicks`+1;";
$result = $conn->query( $sql );
/* retrieve the number of clicks */
$sql="select `clicks` from `clickcounter` where `game_id`='{$id}';";
$result = $conn->query( $sql );
while( $rs=$result->fetch_object() ) $clicks=intval( $rs->clicks );
echo 'Total clicks: '.$clicks;
?>