DMZ 1.7.1 (DataMapper OverZealous Edition)

[eluser]bojack[/eluser]
[quote author="OverZealous" date="1270759431"]Assuming the queries are returning the exact same results, try using include_related without instantiating, and see if that works. If that works, then most likely something is happening on the server that is causing $posts->_instantiations to be unset or set to NULL.[/quote]

Now we are getting somewhere! Running this on both server works:

Code:

$posts->include_related('category')->get();
foreach ($posts as $p) {
    echo $p->category_title . '<br>';
}

So it seems to be related to the instantiating.

Code:

->include_related('category', NULL, TRUE, TRUE)