如何显示MySQL表的平均值

I have a MySQL database that holds details on various video games and user accounts. A user is able to review a game and the score is put into a review table. I am trying to retrieve the average score for each game and have it displayed on a webpage. My SQL statement within PHP looks like this

$sqlOverall = "SELECT CAST(AVG('scoreOverall') AS DECIMAL('10,1')) 
               FROM 'ratings' 
               WHERE gameID = '$id'";
$scoreOverall = mysqli_query($conn, $sqlOverall);

But when I try to echo $scoreOverall it returns blank.

try this below query

$selquery="SELECT CAST(AVG(scoreOverall) AS DECIMAL(10,1)) FROM ratings WHERE gameID='$id'";
$result= mysqli_query($conn, $selquery);
SELECT CAST(AVG(scoreOverall) AS DECIMAL(10,1)) 
               FROM ratings 
               WHERE gameID = '$id';

Try above code. Hope this will helps.

It works fine. Hope it is your helpful

$sqlOverall="SELECT CAST(AVG(scoreOverall) AS DECIMAL(10,1)) FROM ratings WHERE gameID=$id";
$scoreOverall = mysqli_query($conn, $sqlOverall);
foreach ($scoreOverall as $value) { 
    $scoreOverall = $value['CAST(AVG(queue_status) AS DECIMAL(10,1))']; 
    echo $scoreOverall;
}