I'm in learning mode here, very new to PHP, so I'm working with a code sample.
Please forgive my use of 'global' here, but I want to understand php variable scoping.

**Here is myGlobals.php:**

```
<?php 
     global $db_server;
   // other code not shown
?>

```

**Here is connectToDb.php:**

```
<?php
      require_once 'myGlobals.php';

      // no declared functions in this file, all inline code
      $db_server = mysql_connect(.....);
      mysql_select_db( "theDatabase", $db_server);
?>

```

**Here is addDbRecords.php:**

```
<?php
       require_once 'myGlobals.php';

       // other inline code.....
       doAddDeleteRecord($db_server);

function doAddDeleteRecord($db_server)
{
  //global $db_server;

  if( !mysql_query($query, $db_server))
   {
         // handle the error...
   }
 }
?>

```

**Here is index.php:**

```
<?php
      require_once 'myGlobals.php';
      require_once 'connectToDb.php';
      require_once 'addDbRecords.php';

     // this is simplified, just trying to show that everything in inline code
 ?>

```

Here is the problem. When I call `doAddDeleteRecord($db_server)` inside the file addDbRecords.php 
above, `$db_server` is not valid -- it is null -- when I call `mysql_query(.., $db_server, ...)` -- this is the error message:

> 
> "Warning: mysql\_query() expects
>  parameter 2 to be resource, null given
>  in C:\xampp\htdocs\addDbRecords.php on
>  line 29" 
> 
> 
> 

So I tried using the 'global' declaration inside `doAddDeleteRecord()` (commented out above) -- no change.  

The `mysql_query(...)` still fails with a NULL value for `$db_server`.

I know the `mysql_connect(....)` works because other code pulls all my records out of my database successfully (using a SELECT) and the existing records get displayed correctly in the browser.

So in my opinion, the fact that `$db_server` is declared with 'global' should mean that the scope of `$db_server` is such that once `mysql_connect(...)` is called -- at file scope in all my files, `$db_server` will be a valid connection to my database.

I'm only trying to learn about **php scoping**, not OOAD or anything else (for now). Why is `$db_server()` null here?