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Hi, if I do the following I am receiving lots of results:

$t = Title::newFromText("Main_Page"); 
$dbr = wfGetDB(DB_SLAVE);
while ($row = $dbr->fetchObject(Revision::fetchRevision($t))) {
  var_dump($row);
}

However, doing the following I am only receving a single result:

$t = Title::newFromText("Main_Page");
$r = Revision::fetchRevision($t);
$dbr = wfGetDB(DB_SLAVE);
while ($row = $dbr->fetchObject($r)) {
  var_dump($row);
}

The same here:

$dbr = wfGetDB(DB_SLAVE);
$t = Title::newFromText("Main_Page");
$r = ResultWrapper ($dbr, Revision::fetchRevision($t));
while ($row = $dbr->fetchObject($r)) {
  var_dump($row);
}

And to top it, if I change the code at top to the following, I receive the output "1", too:

$t = Title::newFromText("Main_Page"); 
print Revision::fetchRevision($t)->numRows();

Can somebody explain why it is this inconsistent? Is there something I'm doing wrong?