<?php
$data = <<<DATA
<html>
<head/>
<body>
<table id="two_rows">
<tr><td>One column</td></tr>
<tr><td>Another column</td></tr>
</table>
<table id="one_row">
<tr><td>One column</td></tr>
</table>
</body>
</html>
DATA;
$dom = new DOMDocument();
$dom->loadHTML($data);
$xpath = new DOMXPath($dom);
$tables = $xpath->query("//table[count(tr) = 1]");
?>
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