PHP Undefined variable in functions and included scripts

Question

I\'ve read a LOT of things about this problem, however I still cannot fix it.

In my functions file I declare a variable with a value like so:

$px_host =          


        

Answer 1

It's getting late, so this is only a partial answer.

Another approach you could take is to pass the database instance into your helper function, thus resolving the credentials issue.

function dbQuery($database, $reqquery)
{
    if (false !== ($query = mysql_query($reqquery, $database))) {
        exit("Error - query error.");
    }

    return $query;
}

Now this function receives its dependency via the arguments and is also a lot shorter and doesn't connect / query / disconnect every time.

The remaining code has to be written elsewhere; if you require a database at every page, you can write this pretty high up the chain:

if (false === ($connect = mysql_connect($px_host, $px_dbuser, $px_dbpass))) {
    exit("Error - cannot connect to MySQL server - " . mysql_error());
}

if (false === mysql_select_db($database)) {
    exit("Error - cannot select database - " . mysql_error());
}

Then you pass $connect around wherever it's required.

$res = dbQuery($connect, 'SELECT "hello world"');

Of course, mysql_connect and friends use implied connections, so you technically don't need to pass it around anyway; it's a good pattern nonetheless.

Last but not least

Learn how to use PDO and revel in the magical world of OOP ;-)