MySQL PHP for SELECT AVG(column) returns Resource ID 3

Question

I want to get the average value of my ratings column for my review table. This is what has been done so far

$averagereviewquery = "SELECT AVG(review_rating) from reviews where product_id=".$primarykey;               
$averagereviewresult=mysql_query($averagereviewquery);

                if($insert_review){ //successful insert
                    echo $averagereviewresult;
                }

what happens is averagereviewresult returns "Resource Id 3". What do i do to change it to show me the average value?

Answer 1

mysql_query does return a resource. You need to expicitly read the value from your query in order to get the result. One way is to use mysql_result :

echo mysql_result($averagereviewresult, 0);

Answer 2

You missed fetching the actual data

$result = mysql_result($averagereviewquery, 0);

Answer 3

You need extract the result in to an array first.

$averagereviewquery = "SELECT AVG(review_rating) from reviews where product_id=".$primarykey;               
$averagereviewresult=mysql_query($averagereviewquery);

if($insert_review){ //successful insert
        $row = mysql_fetch_array($averagereviewresult);

        echo $row[AVG(review_rating)];
}

Answer 4

SELECT AVG(review_rating) AS review_rating_avg ...