How to get the result of a select count(*) query in PHP?

Question

I have this query to use in PHP:

mysql_query("select count(*) from registeredUsers where email=".$_SESSION["username"]);

When I use echo to print out the result, nothing gets printed. What exactly is the return value from the above statement?

Answer 1

Your code doesn't include any fetch statement. And as another answer notes, you need single quotes around $_SESSION["username"].

$result = mysql_query("select count(*) from registeredUsers where email='{$_SESSION['username']}'");

// Verify it worked
if (!$result) echo mysql_error();

$row = mysql_fetch_row($result);

// Should show you an integer result.
print_r($row);

Answer 2

mysql_query returns a result resource. You can read the result with mysql_result

$res = mysql_query("select count(*) from registeredUsers where email='".mysql_real_escape_string($_SESSION["username"])."'");
echo mysql_result($res,0);

Answer 3

You need single quotes around the session variable in your query

$result = mysql_query("SELECT COUNT(*) 
                       FROM registeredUsers 
                       WHERE email = '".$_SESSION['username']."' ");