在PHP代码中输出v $ session（来自oracle DB）

I am using oracle db and I want to output the count of v$session in my php code. But when I run it, php reads it as a variable because of "$". Can anyone help me? Thanks!

This is my code:

        $sql = "select COUNT(*) SID from v$session";   
        $array = oci_parse($conn, $sql);
        oci_execute($array);

        $row = oci_fetch_array($array);
        echo $row;

Error: Notice: Undefined variable: session in C:\xampp\htdocs\test\index.php on line 12

you should change double quotes to single quotes like :

$sql = 'select COUNT(*) SID from v$session';

Here is some examples :

Strings with double quotes :

<?php
$name = "ilyas";
 $age = 42
 echo "Hi, my name is $name and I am $age years old.";
?>

this will print :

Hi, my name is ilyas and I am 42 years old.

Strings with single quotes :

<?php
 $name = 'ilyas';
 echo 'Hi, my name is $name mimo.';
?>

this will print :

Hi, my name is $name mimo.