将SQL查询对象转换为整数

Given the code:

$counters = $db->query("SELECT COUNT(film_id) FROM review WHERE film_id = $film_id ");

I need to convert the object $counters into an integer. FYI: the query returns a single int i.e 4 (depending on the film_ID)

Give an alias to the column that stores the COUNT result then use it as you would use with any other SELECT query.

$counters = $db->query("SELECT COUNT(film_id) AS counter FROM review WHERE film_id = $film_id ");
$counter = $counters->fetch_assoc();

echo $counter['counter'];

$counters is not the result string you assume, but a resource object.

My suggestion is to change the code as follows:

$res = $db->query("SELECT COUNT(film_id) as counter FROM review WHERE film_id = $film_id ");
$row = $res->fetch_assoc();
$counter = (int) $row["counter"];